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Using and Configuring Features Version 3.4


Configuring and Monitoring the Network Dispatcher Feature

This chapter describes the Network Dispatcher Feature configuration and operational commands. It contains the following sections:


Accessing the Network Dispatcher Configuration Commands

To access the Network Dispatcher configuration environment:

  1. Enter talk 6 at the OPCON prompt (*).
  2. Enter feature ndr at the Config > prompt.

Network Dispatcher Configuration Commands

Table 12 summarizes the Network Dispatcher configuration commands and the rest of the section explains these commands. Enter these commands at the NDR Config > prompt.

Table 12. Network Dispatcher Configuration Commands
Command Function
? (Help) Displays all the commands available for this command level or lists the options for specific commands (if available). See "Getting Help".
Add Configures various components of the Network Dispatcher including advisors, clusters, ports, and servers.
Clear Clears the entire Network Dispatcher configuration.
Disable Disables the backup, executor, and manager components of the Network Dispatcher. Also disables specific advisors.
Enable Enables the backup, executor, and manager components of the Network Dispatcher. Also enables specific advisors.
List Displays the entire Network Dispatcher Configuration or specific portions of the configuration.
Remove Removes specific portions of the Network Dispatcher configuration.
Set Changes the configuration parameters for advisors, clusters, ports, servers, or the Network Dispatcher manager.
Exit Returns you to the previous command level. See "Exiting a Lower Level Environment".

Add

Use the add command to configure advisors, clusters, ports, servers, and reach addresses. For High Availability you can also configure whether this Network Dispatcher is a primary or backup and which IP addresses to use for heartbeat.

Syntax:

add
advisor . . .

backup . . .

cluster . . .

heartbeat . . .

port . . .

reach . . .

server . . .

Advisor name port# interval timeout comm-port
Specifies the name and port for an advisor. This parameter also specifies how frequently the advisor will collect information on a particular protocol and a time period after which the advisor report is considered to be out of date.

name
Specifies the type of advisor. Enter the advisor number that corresponds with the type of advisor you want to add.


Table 13. Advisor Names and Port Numbers
Advisor Number Advisor Name Default Port#
0 FTP 21
1 HTTP 80
2 MVS 10007
3 TN3270 23
4 SMTP 25
5 NNTP 119
6 POP3 110
7 TELNET 23
8 SSL 443

Valid values: 0 - 8

Default value: 1

port#
Specifies the port number for this advisor.

Valid values: 1 to 65535

Default values: See Table 13.

interval
Specifies the frequency, in seconds, with which the advisor queries its protocol for each server. After half of this value without a response from the server, the adviser considers the protocol unavailable.

Valid values: 1 to 65535

Default value: 5

timeout
Specifies the interval of time, in seconds, after which the advisor report is considered to be out of date.

To make sure that out-of-date information is not used by the manager in its load-balancing decisions, the manager will not use information from the advisor whose time stamp is older than the time set in this parameter. The advisor timeout should be larger than the advisor polling interval. If the timeout is smaller, the manager will ignore reports that should be used. By default, advisor reports do not time out.

This timeout value typically applies if you disable an advisor. Do not confuse this parameter with the interval/2 timeout previously described, which relates to a server not responding.

Valid values: 0 to 65535

Default value: 0, which means the advisor report never times out.

comm-port
Specifies the port number used by the TN3270 advisor to communicate with the TN3270 servers. This parameter is input only for the TN3270 advisor. It must match the advisor port number set in the TN3270 server configuration.

Valid values: 1 to 65535

Default value:

  • TN3270 default:10008
Note:Because the manager component is a prerequisite for the advisor, you must enable the manager before any advisor can be enabled. You must also set the manager proportions so that the manager will consider advisor input when setting the server weights that are used to make load balancing decisions. You must also set the internal IP address using the set internal-ip-address command for the advisor to run correctly. See Configuring and Monitoring IP in Protocol Configuration and Monitoring Reference Volume 1 for more information about the set internal-ip-address command.

Example 1:

add advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp,6=pop3,7=telnet,8=SSL) [1]? 1
Port number [80]?
Interval (seconds) [5]? 10
Timeout (0=unlimited) [0]? 10

Example 2:

add advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp,6=pop3,7=telnet,8=SSL) [1]? 3
Port number [23]?
Interval (seconds) [5]? 10
Timeout (0=unlimited) [0]? 10
Communication Port number [10008]?

backup role strategy
Specifies whether this Network Dispatcher is a backup or primary.

role
Defines whether this is a primary or a backup Network Dispatcher. Use this command only if you intend to have a redundant configuration, and want the High Availability function to run. In this case, you must also configure the heartbeat (add heartbeat) and reachability (add reach).

Valid values: 0 or 1

0 = primary

1 = backup

Default value: 0

strategy
Specifies whether the Network Dispatcher will switch back to primary mode automatically or manually. Whenever a Primary Network Dispatcher fails and becomes standby (which means a backup performed the IP takeover function), and then becomes available, it will automatically become the active Network Dispatcher if the strategy is set to automatic. If strategy is set to manual, the old primary will go to standby mode and the operator must use the switchover command in talk 5 to make it active again. See Switchover.

Valid values: 0 or 1

0 = automatic

1 = manual

Default value: 0

Example:

add backup
Role (0=Primary, 1=Backup) [0]?
Switch back strategy (0=Auto, 1=Manual) [0]?

cluster address FIN-count FIN-timeout Stale-timer Advertise-cluster-address Advertise-route-cost
Specifies a cluster's IP address and the frequency for the executor to perform garbage collection from the Network Dispatcher database. If you configure cluster addresses to be advertised, see "Using Network Dispatcher with Cluster Address Advertising" for more information. For cluster addresses that are not configured to be advertised, you must select cluster addresses that are part of an advertised subnet that is local to the Network Dispatcher machine. This would typically be the subnet on which Network Dispatcher receives client traffic from the next hop router.
Note:Cluster IP Addresses must not match the internal IP address of the router and must not match any interface IP addresses defined on the router. If you are running Network Dispatcher and TN3270 server in the same machine, the cluster address can match an IP address defined on the loopback interface. See "Using Network Dispatcher with TN3270 Server" for more information.

address
Specifies the IP address for the cluster.

Valid values: Any valid IP address

Default value: 0.0.0.0

FIN-count
Specifies the number of connections that must be in FIN state before the executor tries to remove the unused connection information from the Network Dispatcher database after FIN-timeout or Stale-timer has elapsed.

Valid Values: 0 to 65535

Default value: 4000

FIN-timeout
Specifies the number of seconds, that a connection has been in the FIN state, after which the executor tries to remove the unused connection information from the Network Dispatcher database.

Valid Values: 0 to 65535

Default value: 30

Stale-timer
Specifies the number of seconds, that a connection has been inactive, after which the executor tries to remove a connection's information from the Network Dispatcher database.

Valid Values: 0 to 65535

Default value: 1500

Advertise-cluster-address
Specifies whether the cluster address should be advertised.

Valid Values: yes or no

Default value: no

Advertise-route-cost
Specifies the cost of the advertised route. This question is asked only if the answer to advertise cluster address is yes.

Valid Values: 0 to 4294967295

Default value: 0

Example:

NDR Config>add cluster
Cluster Address [0.0.0.0]? 113.3.1.12
FIN count [4000]? 
FIN time out [30]? 
Stale timer [1500]? 
Advertise cluster address [No]? y
Advertise route cost [0]? 20
Cluster 113.3.1.12 has been added.
Fincount has been set to 4000 for cluster 113.3.1.12
Fintimeout has been set to 30 for cluster 113.3.1.12
Staletimer has been set to 1500 for cluster 113.3.1.12
NDR Config>

heartbeat address1 address2
Specifies one path for Heartbeat messages. The Heartbeat message will flow from address1, which belongs to this Network Dispatcher, to address2, which belongs to the peer Network Dispatcher.
Note:Configuring more than one heartbeat path between the primary and backup Network Dispatchers is required to ensure that the failure of a single interface will not disrupt the heartbeat communication between the primary and backup machines.

If you have only one existing LAN connection between the two Network Dispatchers, the second heartbeat could be set up over a simple LAN connection (a crossover cable used directly between two Ethernet ports) or a point-to-point serial connection (back-to-back PPP connection over a null-modem cable using unnumbered IP).

address1
Specifies the IP address of the interface of this Network Dispatcher from which Heartbeat messages will flow.

Valid Values: Any IP address.

Default value: 0.0.0.0

address2
Specifies the IP address of the interface of the peer Network Dispatcher to which Heartbeat messages will flow. This address must be reachable from the interface specified in address1.

Valid Values: Any IP address.

Default value: 0.0.0.0

Example:

add heartbeat
Source Heartbeat address [0.0.0.0]? 131.2.25.90
Target Heartbeat Address [0.0.0.0]? 131.2.25.92

port cluster-address port# port-type max-weight port-mode
Specifies the port and port's attributes.

cluster-address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

port#
Specifies the port number of the protocol for this cluster.

Valid Values: 1 to 65535

Default value: 80

port-type
Specifies the types of IP traffic that can be load balanced on this port. Supported types are:
  • 1 = TCP
  • 2 = UDP
  • 3 = both

Valid Values: 1, 2, 3

Default value: 3

max-weight
Specifies the maximum weight for servers on this port. This affects how much difference there can be between the number of requests the executor will give each server.

Valid Values: 0 to 100

Default value: 20

port-mode
Specifies whether the port will feed all requests from a single client to a single server (known as sticky), use passive ftp (pftp), feed an external scalable cache array (extcache), or use no particular protocols on this cluster (none).

Valid Values: 0, 1, 2, 4,, where:

  • 0 = none
  • 1 = sticky
  • 2 = pftp
  • 4 = extcache

Default value: 0

Example:

Config>feature ndr
NDR>add cluster 1.2.3.4 4000 30 1500
NDR>add port
Cluster address [0.0.0.0]? 1.2.3.4
Port number [80]? 80
Port type [3]?
Maximum weight [20]?
Port mode [0=none, 1=sticky, 2=pftp, 4=extcache ]? 0
 

reach address
Specifies any host address that the Network Dispatcher must be able to reach to run correctly. It can be a server address, a router address, an administration station address or other IP host.

address
Specifies the target IP address.

Valid Values: Any IP address

Default value: 0.0.0.0

Example:

add reach
Address to reach [0.0.0.0]? 

server cluster-address port# server-address server-weight server-state
Specifies the attributes of a server in a cluster.

cluster-address
Specifies the IP address of the cluster to which this server belongs.

Valid Values: Any IP address

Default value: 0.0.0.0

port#
Specifies the protocol running over the connection to this server.

Valid Values: 1 to 65535

Default value: 80

server-address
Specifies the IP address of the server.

Valid Values: Any IP address

Default value: 0.0.0.0

server-weight
Specifies the weight of the server for the executor. This affects how frequently the Network Dispatcher sends requests to this particular server.

Valid Values: 0 to the value of max-weight specified on the add port command.

Default value: max-weight on port command

server-state
Specifies whether the executor should regard the server as available or unavailable when the executor begins processing.

Valid Values: 0 (down) or 1 (up)

Default value: 1

Example:

add server
Cluster address [0.0.0.0]? 131.2.25.91
Port number [80]? 80
Server address [0.0.0.0]? 131.2.25.94
Server weight [35]?
Server state (down=0 up=1) [1]? 

Parameter Configuration Limits

Table 14 lists the limits for the various items you can configure for a Network Dispatcher.

Table 14. Parameter Configuration Limits
Parameter Limit
Advisors 8 per 2210
Clusters 32 per 2210
Heartbeats 8 per 2210
Ports 8 per cluster
Reachs 8 per 2210
Servers 32 per configured port, 128 for each port number under all clusters configured.
Unique server IP addresses 32 per 2210

Clear

Use the clear command to clear the entire Network Dispatcher configuration.

Syntax:

clear
 

Disable

Use the disable command to disable a Network Dispatcher component.

Syntax:

disable
advisor . . .

backup

executor

manager

advisor name port#
Disables an advisor from the Network Dispatcher.

name
Specifies the type of advisor. Enter the advisor number that corresponds with the type of advisor you want to disable.

See Table 13 for additional information.

Valid values: 0 - 8

Default value: 0

port#
Specifies the port number for this advisor.

Valid values: 1 to 65535

Default value: None. You must enter a port number.

Example:

disable advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp,6=pop3,7=telnet,8=SSL) [1]? 1
Port number [0]? 80

backup
Disables the Network Dispatcher's backup function.

Example:

disable backup
Backup is now disabled.

executor
Disables the Network Dispatcher executor. Disabling the executor disables the Network Dispatcher feature.

Example:

disable executor
Executor is now disabled.
Note:Disabling the executor will stop the manager, advisors, and the high availability function, if they are currently running.

manager
Disables the Network Dispatcher manager. The manager is an optional component. However, if you do not use the manager, the Network Dispatcher will balance the load using a round-robin scheduling method based on the current server weights.

Example:

disable manager
Manager is now disabled.
Note:Because the manager component is prerequisite for advisors, disabling the manager will stop all the advisors from running.

Enable

Use the enable command to enable a Network Dispatcher component.

Syntax:

enable
advisor . . .

backup

executor

manager

advisor name port#
Enables an advisor to the Network Dispatcher.

name
Specifies the type of advisor. Enter the advisor number that corresponds with the type of advisor you want to enable.

See Table 13 for additional information.

Valid values: 0 - 8

Default value: 0

port#
Specifies the port number for this advisor.

Valid values: 1 to 65535

Default value: None. You must enter a port number.

Example:

enable advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp=6=pop3,7=telnet,8=SSL) [1]? 1
Port number [0]? 80
Note:Because the manager component is a prerequisite for the advisor, you must enable the manager before any advisor can be enabled. You must also set the manager proportions so that the manager will consider advisor input when setting the server weights that are used to make load balancing decisions. You must also set the internal IP address using the set internal-ip-address command for the advisor to run correctly. See the chapter Configuring and Monitoring IP in Protocol Configuration and Monitoring Reference Volume 1 for more information about the set internal-ip-address command.

backup
Enables the Network Dispatcher's backup function.

Example: enable backup
Note:Before enabling backup, you must add at least one heartbeat

executor
Enables the Network Dispatcher executor.

Example:

enable executor
Executor is now enabled.

manager
Enables the Network Dispatcher manager.

Example:

enable manager
Manager interval was set to 2.                     
Manager proportions were set to  50   50   0   0   
Manager refresh cycle was set to 2                 
Manager sensitivity was set to 5.                  
Manager smoothing factor was set to 1.50.          
                                                   
                                

When the manager is enabled for the first time, a manager record is created with the following default values:

Interval:
2 seconds

Refresh-Cycle:
2

Sensitivity:
5 %

Smoothing:
1.5

Proportions:

Active:
50%

New:
50%

Advisor:
0

System:
0

See Set for a description of the above parameters.

List

Use the list command to display information about the Network Dispatcher.

Syntax:

list
all

advisor

backup

cluster

manager

port

server

all
Displays all Network Dispatcher configuration information. This includes the same information displayed for advisors, backup, cluster, manager, ports, and servers.

Example:

NDR Config> list all
 
Executor: Enabled
 
Manager: Enabled
 
        Interval        Refresh-Cycle   Sensitivity     Smoothing
        2               2               5 %             1.50
        Proportions:    Active  New     Advisor         System
                        50 %    50 %    0 %             0 %
 
Advisor:
        Name    Port    Interval        TimeOut         State     CommPort
        http    80      5               0               Enabled
        MVS     10007   15              0               Enabled
        TN3270  23      5               0               Enabled   10008
 
Backup: Enabled
        Role            Strategy
        PRIMARY         AUTOMATIC
 
        Reachability:   Address         Mask            Type
                        131.2.25.93     255.255.255.255 HOST
                        131.2.25.94     255.255.255.255 HOST
 
        HeartBeat Configuration:
           Source Address:  131.2.25.90 Target Address:   131.2.25.92
           Source Address:  132.2.25.90 Target Address:   132.2.25.92
 
Clusters:
        Cluster-Addr    FIN-count       FIN-timeout     Stale-timer  Advertise/Cost
        131.2.25.91     4000            30              1500         Yes      / 20
 
Ports:
  Cluster-Addr    Port#   Weight  Port-Mode  Port-Type  
  131.2.25.91     23      20 %    none       TCP        
  131.2.25.91     80      20 %    none       Both       
         
Servers:
        Cluster-Addr    Port#   Server-Addr     Weight  State
        131.2.25.91     23      131.2.25.93     20 %    up
        131.2.25.91     23      131.2.25.94     20 %    up
        131.2.25.91     80      131.2.25.93     20 %    up
        131.2.25.91     80      131.2.25.94     20 %    up

advisor
Displays the configuration for the Network Dispatcher advisors.

backup
Displays the backup configuration for the Network Dispatcher.

cluster
Displays the configuration of the Network Dispatcher clusters.

manager
Displays the configuration of the Network Dispatcher manager.

port
Displays the configuration of the Network Dispatcher ports.

server
Displays the configuration of the servers associated with the Network Dispatcher clusters.

Remove

Use the remove command to delete part of the Network Dispatcher configuration.

Syntax:

remove
advisor . . .

backup

cluster . . .

heartbeat . . .

port . . .

reach . . .

server . . .

advisor name port#
Removes a specific advisor from the Network Dispatcher configuration.

name
Specifies the type of advisor. Enter the advisor number that corresponds with the type of advisor you want to remove.

See Table 13 for additional information.

Valid values: 0 - 8

Default value: 0

port#
Specifies the port number for this advisor.

Valid values: 1 to 65535

Default value: None. You must enter a port number.

Example:

remove advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp,6=pop3,7=telnet,8=SSL) [0]?
Advisor port [0]? 80

backup
Removes the high availability function.
Note:Because backup is a prerequisite for the heartbeat and reach functions removing backup will stop heartbeat and reach from running.

Example: remove backup

cluster address
Removes a cluster from the Network Dispatcher configuration.

address
Specifies the IP address for the cluster.

Valid values: Any valid IP address

Default value: 0.0.0.0

Note:Removing a cluster address also removes all the ports and servers associated with that cluster.

Example:

remove cluster
WARNING: Deleting a cluster will make any port or server
         associated with it to also be deleted.
Cluster address [0.0.0.0]? 131.2.25.91

heartbeat address
Removes the heartbeat address from the Network Dispatcher configuration.

address
Specifies the IP address for the target Network Dispatcher.

Valid values: Any valid IP address

Default value: 0.0.0.0

Example:

remove heartbeat
Target address [0.0.0.0]? 131.2.25.92

port cluster-address port#
Removes a port from a specific cluster in the Network Dispatcher configuration.

cluster-address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

port#
Specifies the port number of the protocol for this cluster.

Valid Values: 1 to 65535

Default value: None. You must enter a port number.

Example:

remove port
WARNING: Deleting a port will make any server 
associated with it also be deleted.   [0.0.0.0]? 7.82.142.15
Port number [0]? 80
Cluster address [0.0.0.0]? 20.21.22.15

reach address
Removes a server from the list of hosts the Network Dispatcher must be able to reach.

address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

Example:

remove reach
Target address [0.0.0.0]? 9.82.142.15

server cluster-address port# server-address
Removes a server from a cluster and port in the Network Dispatcher configuration.

cluster-address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

port#
Specifies the port number of the protocol for this cluster.

Valid Values: 1 to 65535

Default value: None. You must enter a port number.

server-address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

Example:

remove server
Cluster address [0.0.0.0]? 7.82.142.15
Port number [0]? 80
Server address [0.0.0.0]? 20.21.22.15

Set

Use the set command to change the attributes of an existing advisor, cluster, port, or server. You can also define attributes for the Network Dispatcher manager.

Syntax:

set
advisor . . .

cluster . . .

manager . . .

port . . .

server . . .

advisor name port# interval timeout comm-port
Changes the port number, interval, and timeout for an advisor.

name
Specifies the type of advisor. Enter the advisor number that corresponds with the type of advisor you want to set.

See Table 13 for additional information.

Valid values: 0 - 8

Default value: 0

port#
Specifies the port number for this advisor.

Valid values: 1 to 65535

Default value: None. You must enter a port number.

interval
Specifies the frequency with which the advisor queries its protocol for each server. After half of this value expires without a response from the server, the adviser considers the protocol unavailable.

Valid values: 0 to 65535

Default value: 5

timeout
Specifies the interval of time, in seconds, after which the advisor considers the protocol unavailable.

To make sure that out-of-date information is not used by the manager in its load-balancing decisions, the manager will not use information from the advisor whose time stamp is older than the time set in this parameter. The advisor timeout should be larger than the advisor polling interval. If the timeout is smaller, the manager will ignore reports that should be used. By default, advisor reports do not time out.

This timeout value typically applies if you disable an advisor. Do not confuse this parameter with the interval/2 timeout previously described, which relates to a server not responding.

Valid values: 0 to 65535

Default value: 0, which means the protocol is considered always available.

comm-port
Specifies the port number used by the TN3270 advisor to communicate with the TN3270 servers. This parameter is input only for the TN3270 advisor.

Valid values: 1 to 65535

Default value:

  • TN3270 default:10008

Example:

set advisor
Advisor name (0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp=6=pop3,7=telnet,8=SSL) [0]?
Port number [0]? 21
Interval (seconds) [5]? 10
Timeout (0=unlimited) [0]? 20
 

cluster address FIN-count FIN-timeout Stale-timer
Changes the FIN-count, FIN-timeout, and Stale-timer for a cluster in the Network Dispatcher configuration.

address
Specifies the IP address for the cluster.

Valid values: Any valid IP address

Default value: 0.0.0.0

FIN-count
Specifies the number of connections that must be in FIN state before the executor tries to remove the unused connection information from the Network Dispatcher database after FIN-timeout or Stale-timer has elapsed.

Valid Values: 0 to 65535

Default value: 4000

FIN-timeout
Specifies the number of seconds after which the executor tries to remove the unused connection information from the Network Dispatcher database.

Valid Values: 0 to 65535

Default value: 30

Stale-timer
Specifies the number of seconds that a connection has been inactive, after which the executor tries to remove a connection's information from the Network Dispatcher database.

Valid Values: 0 to 65535

Default value: 1500

Example:

set cluster
Cluster address [0.0.0.0]? 131.2.25.91
FIN count [4000]? 4500
FIN timeout [30]? 40
Stale timer [1500]? 2000

manager interval proportion refresh sensitivity smoothing
Sets the values that the manager uses to determine the best server to satisfy a request.

interval
Specifies the amount of time, in seconds, after which the manager Updates the server weights that the executor uses in load balancing connections.

Valid values: 0 to 65535

Default value: 2

proportion
Specifies the relative importance of external factors in the manager's weighting decisions. The sum of the proportions must equal 100. The factors are:

active
The number of active connections on each TCP/IP server as tracked by the executor.

Valid values: 0 to 100

Default value: 50

new
The number of new connections on each TCP/IP server as tracked by the executor.

Valid values: 0 to 100

Default value: 50

advisor
Input from the protocol advisors defined to the Network Dispatcher.

Valid values: 0 to 100

Default value: 0

system
Input from the MVS system advisor provided by the MVS WLM system monitoring tool.

Valid values: 0 to 100

Default value: 0

refresh
Specifies the frequency with which the manager requests status from the executor. This parameter is specified as a number of intervals.

Valid values: 0 to 100

Default value: 2

sensitivity
Specifies the percentage weight change for all the servers on a port, after which the manager updates the weights that the executor uses in load balancing connections.

Valid values: 0 to 100

Default value: 5

smoothing
Specifies a limit to the amount that a server's weight can change. Smoothing minimizes the frequency of change in the distribution of requests. A higher smoothing index will cause the weights to change less. A lower smoothing index will cause the weights to change more.

Valid values: a decimal value between 1.0 and 42 949 673.00

Default value: 1.5
Note:You can only specify two places after the decimal point.

Example:

set manager
Interval (in seconds) [2]? 3
Active proportion [50]? 40
New proportion [50]? 38
Advisor proportion [0]? 20
System proportion [0]? 2
Refresh cycle [2]? 4
Sensitivity threshold [5]? 10
Smoothing index (>1.00) [1.50]? 200

port cluster-address port# port-type max-weight port-mode
Changes the port-type, max-weight, and port-mode for a specific cluster and port number.

cluster-address
Specifies the IP address of the cluster.

Valid Values: Any IP address.

Default value: 0.0.0.0

port#
Specifies the port number of the protocol for this cluster.

Valid Values: 1 to 65535

Default value: None. You must enter a port number.

port-type
Specifies the type of IP traffic that can be load balanced on this port.

Valid Values:

  • 1 = TCP
  • 2 = UDP
  • 3 = both

Default value: 3

max-weight
Specifies the weight for servers on this port. This affects how much difference there can be between the number of requests the executor will give each server.

Valid Values: 0 to 100

Default value: 20

port-mode
Specifies whether the port will feed all requests from a single client to a single server (known as sticky), use passive ftp (pftp), feed an external scalable cache array, or use no protocols on this cluster (none).

Valid Values:

  • 0 = none
  • 1 = sticky
  • 2 = pftp
  • 4 = extcache

Default value: 0 (none)

Example:

set port
Cluster address [0.0.0.0]? 131.2.25.91
Port number [0]? 23
Port type (tcp=1, udp=2, both=3) [0]?
Max. weight (0-100) [20]? 30
Only one pftp port per cluster allowed
Port mode (none=0, sticky=1, pftp=2 extcache=4) []? 

server cluster-address port# server-address weight state
Changes the server state, and server weight for a specific server in a cluster.

cluster-address
Specifies the IP address of the cluster to which this server belongs.

Valid Values: Any IP address

Default value: 0.0.0.0

port#
Specifies the port number of the protocol for this cluster.

Valid Values: 1 to 65535

Default Value: None. You must enter a port number.

server-address
Specifies the IP address of the server.

Valid Values: Any valid server address

Default Value: 0.0.0.0

state
Specifies whether the executor should regard the server as available or unavailable when the executor begins processing.

Valid Values: 0 (down) or 1 (up)

Default value: 1

weight
Specifies the weight of the server for the executor. This affects how frequently the Network Dispatcher sends requests to this particular server.

Valid Values: 0 to the value of max-weight specified on the add port command.

Default value: max-weight on port command

Example:

set server
Cluster address [0.0.0.0]? 131.2.25.91
Port number [0]?
Server address [0.0.0.0]?
Server weight [20]? 25
Server state (down=0, up=1) [1]? 1

Accessing the Network Dispatcher Monitoring Commands

To access the Network Dispatcher monitoring environment:

  1. Enter talk 5 at the OPCON prompt (*).
  2. Enter feature ndr at the GWCON prompt (+).

Network Dispatcher may also be monitored using SNMP. Refer to "SNMP Management" in the Protocol Configuration and Monitoring Reference Volume 1 for more information.


Network Dispatcher Monitoring Commands

Table 15 summarizes the Network Dispatcher monitoring commands and the rest of the section explains these commands. Enter these commands at the NDR > prompt.

Table 15. Network Dispatcher Monitoring Commands
Command Function
? (Help) Displays all the commands available for this command level or lists the options for specific commands (if available). See "Getting Help".
List Displays the currently configured attributes of the advisor, clusters, ports, or servers.
Quiesce Specifies that no more connection request should be sent to a server. Also temporarily stops the heartbeat and reach functions.
Report Displays a report of information related to the advisor and the manager.
Status Displays the current status of the counters, clusters, ports, servers, advisor, manager, and backup.
Switchover Forces a Network Dispatcher that is running in standby mode to become the active Network Dispatcher. Use of this command is necessary if you specified manual as the switchover mode.
Unquiesce Allows the Network Dispatcher manager to assign a weight greater than 0 to a previously quiesced server on every port that the server is configured. This action allows new connection requests to flow to the selected server.
Exit Returns you to the previous command level. See "Exiting a Lower Level Environment".

List

Use the list command to display information about the Network Dispatcher.

Syntax:

list
advisor

cluster

port

server

advisor
Displays the configuration for the Network Dispatcher advisors that are currently enabled..

Example:

list advisor
Advisor list requested.
 
-------------------------------------------
| ADVISOR |  PORT  |  TIMEOUT  |  STATUS  |
-------------------------------------------
|  ftp    |    21  |       5   |   ACTIVE |
|  Http   |    80  | unlimited |   ACTIVE |
|  MVS    | 10007  | unlimited |   ACTIVE |
|  TN3270 |    23  | unlimited |   ACTIVE |
-------------------------------------------

cluster
Displays the configuration of the Network Dispatcher clusters.

Example:

list cluster
EXECUTOR INFORMATION:
 ---------------------
Version: 01.01.00.00 - Tue Dec 10 14:15:58 EST 1996
Number of defined clusters: 2
 
CLUSTER LIST:
-------------
  131.2.25.91
  10.11.12.2

port
Displays the configuration of the Network Dispatcher ports.

Example:

list port
Cluster Address [0.0.0.0]? 131.2.25.91
 
  ---------------------------------------------------------  
 | CLUSTER:       131.2.25.91                            |  
 |-------------------------------------------------------|  
 |   PORT   |    MAXWEIGHT   |  PORT MODE  |  PORT TYPE  |  
 |-------------------------------------------------------|  
 |     23   |         30     |    none     |     TCP     |  
 |     80   |         20     |    none     |     both    |  
 ---------------------------------------------------------  
 
 

server
Displays the configuration of the servers associated with the Network Dispatcher clusters.

Example:

list server
Cluster Address [0.0.0.0]? 131.2.25.91
 
PORT 23 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... TCP
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0 
Active: 0 FIN 0 Complete 0 Status: up Saved Weight: -1 
Address: 131.2.25.94 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0 
Active: 0 FIN 0 Complete 0 Status: up Saved Weight: -1 
PORT 80 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... BOTH
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0 
Active: 0 FIN 0 Complete 0 Status: up Saved Weight: -1 
Address: 131.2.25.94 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0 
Active: 0 FIN 0 Complete 0 Status: up Saved Weight: -1

See page *** for a description of the displayed information.

Quiesce

Use the quiesce command to temporarily stop the heartbeat or reach functions or to specify that no more connection requests should be sent to a server.

Syntax:

quiesce
heartbeat

manager

reach

heartbeat address
Stops the selected path for the heartbeat function. The address is the IP address of the remote network dispatcher to which this Network Dispatcher is sending Heartbeat messages.

Example:

quiesce heartbeat
Remote Address [0.0.0.0]? 131.2.25.94

manager address
Specifies that no more connection requests are to be made to the specified server. Address is the IP address of the server.

Example:

quiesce manager
Server Address [0.0.0.0]? 131.2.25.93

reach address
Stops the Network Dispatcher's polling of the specified address to determine if it is reachable, where address is the IP address that is part of the reachability criteria.

Example:

quiesce reach
Reach Address [0.0.0.0]? 131.2.25.92

Report

Use the report command to display a report of the advisor or manager

Syntax:

report
advisor

manager

advisor type port#
Displays a report of information about a specific advisor.

type
Is the type of advisor. Enter the advisor number that corresponds to the type of advisor. See Table 13 for advisor types.

port#
Is the port number.

Example:

report advisor
0=ftp,1=http,2=MVS,3=TN3270,4=smtp,5=nntp,6=pop3,7=telnet,8=SSL
Advisor name [0]? 1
Port number [0]? 80
 
-------------------------------
|      ADVISOR:     http      |
|      PORT:          80      |
-------------------------------
| 131.2.25.93      |       0  |
| 131.2.25.94      |      16  |
-------------------------------

The value shown for each server address represents:

>= 0
Server load

-1
Advisor could not contact server.

manager
Displays a report of the current manager information.

Example:

report manager
 
----------------------------------
|  HOST TABLE LIST  |   STATUS   |
----------------------------------
|  131.2.25.93      |    ACTIVE  |
|  131.2.25.94      |    ACTIVE  |
----------------------------------
 

The reported information is:

Status
Displays the status of the server address.

Quiesce
Server has been quiesced.

Active
Server has not been quiesced.

 
-------------------------------------------------------------------------------
|131.2.25.91    |WEIGHT | ACTIVE % 50  |  NEW % 50    | PORT %  0 |SYSTEM %  0|
|               --------------------------------------------------------------|
|PORT:   23     |NOW|NEW| WT | CONNECT | WT | CONNECT | WT | LOAD | WT | LOAD |
|-----------------------------------------------------------------------------|
|131.2.25.93    | 10| 10|  10|        0|  10|        0|   0|     0|-999|    -1|
|131.2.25.94    | 10| 10|  10|        0|  10|        0|   0|     0|-999|    -1|
|-----------------------------------------------------------------------------|
|PORT TOTALS:   | 20| 20|    |        0|    |        0|    |     0|    |    -2|
-------------------------------------------------------------------------------
 
 
-------------------------------------------------------------------------------
|131.2.25.91    |WEIGHT | ACTIVE % 50  |  NEW % 50    | PORT %  0 |SYSTEM %  0|
|               --------------------------------------------------------------|
|PORT:   80     |NOW|NEW| WT | CONNECT | WT | CONNECT | WT | LOAD | WT | LOAD |
|-----------------------------------------------------------------------------|
|131.2.25.93    | 10| 10|  10|        0|  10|        1|  16|     0|-999|    -1|
|131.2.25.94    | 10| 10|  10|        0|  10|        1|   3|    16|-999|    -1|
|-----------------------------------------------------------------------------|
|PORT TOTALS:   | 20| 20|    |        0|    |        0|    |    16|    |    -2|
-------------------------------------------------------------------------------
 
 
-------------------------------------------
| ADVISOR |  PORT  |  TIMEOUT  |  STATUS  |
-------------------------------------------
|  http   |    80  | unlimited |   ACTIVE |
|  MVS    | 10007  | unlimited |   ACTIVE |
-------------------------------------------
Manager report requested.
The reported information is:

Weight
The overall weight calculation for this server.

Now
The previous weight assigned to the server.

New
The newest weight assigned to the server.

Active %
The active connection proportion for the overall server weight calculation. The value of this parameter is established using the set manager proportions command. See page ***.

Wt
The weight used for overall weight calculation.

Connect
Number of active connections for this server.

New %
The new connection proportion for the overall server weight calculation. The value of this parameter is established using the set manager proportions command. See page ***.

Wt
The weight used for overall weight calculation.

Connect
Number of new connections for this server.

Port %
The advisor proportion for the overall server weight calculation. The value of this parameter is established using the set manager proportions command. See page ***.

Wt
The weight used for overall weight calculation.

Load
Server load reported by advisor for this server.

System %
The system monitor proportion for the overall server weight calculation. The value of this parameter is established using the set manager proportions command. See page ***.

Wt
The weight used for overall weight calculation.

Load
Server load reported by system monitor.

Status

Use the status command to obtain the status of the advisors, backup, counter, clusters, manager, ports, and servers.

Syntax:

status
advisor

backup

cluster

counter

manager

ports

servers

advisor name port#
Obtains the status of a specific advisor.

name
Specifies the type of advisor. Enter the advisor number that corresponds to the type of advisor. See Table 13 for advisor types.

port#
Is the port number.

Example:

status advisor
0=ftp, 1=http, 2=MVS 3=TN3270, 4=SMTP, 5=NNTP, 6=POP3, 7=TELNET, 8=SSL
Advisor name [0]?
Port number [0]? 21
 
Advisor ftp on port 21 status:
==============================
Interval.................. 10

backup
Obtains the status of the backup function.

Example:

status backup
 Dumping status ...
 Role : PRIMARY   Strategy : AUTOMATIC  State : ND_ACTIVE Sub-State : ND_SYNCHRONIZED
 <<Preferred Target : 132.2.25.92>>
 
 Dumping HeartBeat Status ...
 .....Heartbeat target : 131.2.25.92 Status : UNREACHABLE
 .....Heartbeat target : 132.2.25.92 Status : REACHABLE
 
 Dumping Reachability Status ...
 .....Host:131.2.25.93   Local:REACHABLE
 .....Host:131.2.25.94   Local:REACHABLE

cluster address
Obtains the status of a specified cluster, where address is the IP address of the cluster.

Example:

status cluster
Cluster Address [0.0.0.0]? 131.2.25.91
 
EXECUTOR INFORMATION:
 ---------------------
Version: 01.01.00.00 - Tue Dec 10 14:15:58 EST 1996
 
CLUSTER INFORMATION:
 --------------------
Address......................... 131.2.25.91
Number of target ports.......... 2
FIN clean up count.............. 4000
Connection FIN timeout.......... 30
Active connection stale timer... 1500
Advertise cluster address....... Yes
Advertise route cost............ 20
 
PORT 23 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... TCP
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0  Active:
0 FIN 0 Complete 0 Status: up Saved Weight: -1  Address: 131.2.25.94 Weight:
20 Count: 0 TCP Count: 0 UDP Count: 0  Active: 0 FIN 0 Complete 0 Status:
up Saved Weight: -1  
PORT 80 INFORMATION:
 --------------------
Maximum weight.................. 20
Port type....................... BOTH
Port mode....................... NONE
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 0 TCP Count: 0 UDP Count: 0  Active:
0 FIN 0 Complete 0 Status: up Saved Weight: -1  Address: 131.2.25.94 Weight:
20 Count: 0 TCP Count: 0 UDP Count: 0  Active: 0 FIN 0 Complete 0 Status:
up Saved Weight: -1 

See page *** for definitions of the displayed fields.

counter
Obtains the status of all counters.

Example:

status counter
Internal counters from executor:
--------------------------------
Total number of packets into executor...... 2684
Total packets for cluster processing (C)... 2684
Packets not addressed to a cluster(port)... 0
 
Cluster processing results:
---------------------------
Errors..................................... 0
Discarded.................................. 0
Own address.................................0
Forward requested.......................... 2684
Forward discarded with error............... 0
 
Other processing problems:
--------------------------
Total packets dropped (C).................. 0

manager
Obtains the status of the manager.

Example:

status manager
Number of defined hosts... 2
Sensitivity............... 0%
Smoothing factor.......... 2
Interval.................. 3
Weights refresh cycle..... 4
 
Active connections gauge proportion......... 40%
New connections counter(delta) proportion... 38%
Advisor gauge proportion.................... 20%
System Metric proportion....................  2%
 
Manager status requested.

port cluster-address port#
Obtains the status of a specific port, where:

cluster-address
is the IP address of the cluster.

port#
is the port number on the cluster.

Example:

status port
Cluster Address [0.0.0.0]? 131.2.25.91
Port number  [0]? 80
 
PORT 80 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... BOTH
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 12345 TCP Count: 10000 UDP count 2345 
Active: 3431 FIN 3780 Complete 3431 Status: up Saved Weight: -1
Address: 131.2.25.94 Weight: 20 Count: 7890  Active: 2980 FIN 2390 Status: up 
Saved Weight: -1
 

The reported server information is:

Address
Server IP address

Weight
Weight currently assigned to this server

Count
Cumulative count of TCP connections and UDP packets

TCP Count
Cumulative count of TCP connections

UDP Count
Cumulative count of UDP packets

Active
Number of active TCP connections

FIN
TCP connections is FIN state

Complete
TCP connections that are complete (ACK seen after FIN)

Status
Configured server state:

active
The server is active.

down
The server is down.

quiesced
The server is quiesced.

not responding
The server is not responding to the advisor.

Saved weight
Server weight prior to server being marked down

server address
Obtains the status of a specific server, where address is the IP address of the cluster to which the server belongs.

Example:

status server
Cluster Address [0.0.0.0]? 131.2.25.91
 
PORT 23 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... TCP
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 140 TCP Count: 100 UDP Count: 40  
Active: 50 FIN 45 Complete 50  Status: up Saved Weight: -1
Address: 131.2.25.94 Weight: 20 Count: 250 TCP Count: 100 UDP Count: 40  
Active: 60 FIN 54 Complete 50  Status: up Saved Weight: -1
 
PORT 80 INFORMATION:
 --------------------
Maximum weight.................. 20
Port mode....................... NONE
Port type....................... BOTH
All up nodes are weight zero.... FALSE
Total target nodes.............. 2
Currently marked down........... 0
Servers providing service to this port:
Address: 131.2.25.93 Weight: 20 Count: 12345 TCP Count: 10000 UDP Count: 2345  
Active: 3431 FIN 3780 Complete 3431  Status: up Saved Weight: -1
Address: 131.2.25.94 Weight: 20 Count: 7890  TCP Count: 10000 UDP Count: 2345  
Active: 2980 FIN 2390 Complete 3431  Status: up Saved Weight: -1
 

Switchover

Use the switchover command to force a Network Dispatcher that is running in standby mode to become the active Network Dispatcher when the switchover strategy is manual. This command must be entered on the host that is running the Network Dispatcher that is in standby mode.

Syntax:

switchover
 

Unquiesce

Use the unquiesce command to restart a heartbeat, manager, or reach function that was previously stopped with the quiesce command.

Syntax:

unquiesce
heartbeat

manager

reach

heartbeat address
Restarts the path for Heartbeat messages, where address is the IP address of the remote network dispatcher to which this Network Dispatcher is sending Heartbeat messages.

Example:

unquiesce heartbeat
Remote Address [0.0.0.0]? 9.10.11.1

manager address
Restarts sending connection requests to the specified server. Address is the IP address of the server.

Example:

unquiesce manager
Server Address [0.0.0.0]? 20.21.22.15

reach address
Restarts the Network Dispatcher's polling of the specified address to determine if it is reachable, where address is the IP address that is part of the reachability criteria.

Example:

unquiesce reach
Reach address [0.0.0.0]? 20.3.4.5

Network Dispatcher Dynamic Reconfiguration Support

This section describes dynamic reconfiguration (DR) as it affects Talk 6 and Talk 5 commands.

CONFIG (Talk 6) Delete Interface

The CONFIG (Talk 6) delete interface command is not applicable for NDR. Network Dispatcher is a feature and is not configured on an interface.

GWCON (Talk 5) Activate Interface

The GWCON (Talk 5) activate interface command is not applicable for NDR. Network Dispatcher is a feature and is not configured on an interface.

GWCON (Talk 5) Reset Interface

The GWCON (Talk 5) reset interface command is not applicable for NDR. Network Dispatcher is a feature and is not configured on an interface.

CONFIG (Talk 6) Immediate Change Commands

NDR supports the following CONFIG commands that immediately change the operational state of the device. These changes are saved and are preserved if the device is reloaded, restarted, or you execute a dynamically reconfigurable command.
Commands
CONFIG, feature ndr, add advisor
CONFIG, feature ndr, add backup
CONFIG, feature ndr, add cluster
CONFIG, feature ndr, add heartbeat
CONFIG, feature ndr, add port
CONFIG, feature ndr, add reach
CONFIG, feature ndr, add server
CONFIG, feature ndr, disable advisor
CONFIG, feature ndr, disable backup
CONFIG, feature ndr, disable executor
Note:When executor is disabled, it removes all clusters, ports and servers from the runtime code structures, but NOT SRAM.
CONFIG, feature ndr, disable manager
CONFIG, feature ndr, enable advisor
CONFIG, feature ndr, enable backup
CONFIG, feature ndr, enable executor
CONFIG, feature ndr, enable manager
CONFIG, feature ndr, remove advisor
CONFIG, feature ndr, remove backup
CONFIG, feature ndr, remove cluster
Note:Removing a cluster causes all ports and servers associated with that cluster to be removed from the runtime code structures and SRAM.
CONFIG, feature ndr, remove heartbeat
CONFIG, feature ndr, remove port
CONFIG, feature ndr, remove reach
CONFIG, feature ndr, remove server
CONFIG, feature ndr, set advisor
CONFIG, feature ndr, set cluster
CONFIG, feature ndr, set manager
CONFIG, feature ndr, set port
CONFIG, feature ndr, set server

Non-Dynamically Reconfigurable Commands

All NDR configuration parameters can be changed dynamically.


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