Enables (VIPADISTRIBUTE DEFINE) or disables (VIPADISTRIBUTE DELETE) the sysplex distributor function for a dynamic VIPA (defined on the same stack by a VIPADEFINE or VIPABACKUP statement) for which new connection requests can be distributed to other stacks in the sysplex. If you want to distribute FTP traffic, specify port 21 (or another designation according to which ports you are using for FTP) on the PORT parameter.
Rule: Specify the parameters in the order shown here, except for the optional parameters preceding the IPv4 address or IPv6 interface name, which can be specified in any order.
>>-VIPADISTribute--+-| Base Parameters |--+-------------------->< +-| Tier1 Parameters |-+ '-| Tier2 Parameters |-' Base Parameters |--| Base Options |--+-ipv4_addr-----+--------------------------> '-ipv6_intfname-' >--+-----------------------+------------------------------------> | .-------------. | | V | | '-PORT----+-num-----+-+-' '-num-num-' >--DESTIP--+-ALL-------------------------------------------------+--| | .-------------------------------------------------. | | V | | '---dynxcfip--+-----------------------------------+-+-' +-| DESTIP WEIGHTEDACTIVE options |-+ '-| DESTIP HOTSTANDBY options |-----' Base Options (These can be specified in any order) .-DEFINE-. |--+--------+---------------------------------------------------> '-DELEte-' .-DISTMethod BASEWLM -| BASEWLM distribution method options |------------. >--+------------------------------------------------------------------------+--> '-DISTMethod--+-ROUNDROBIN---------------------------------------------+-' +-SERVERWLM -| SERVERWLM distribution method options |---+ +-WEIGHTEDActive-----------------------------------------+ '-HOTSTANDBY -| HOTSTANDBY distribution method options |-' .-NOOPTLOCAL----------. >--+---------------------+--+--------------+--------------------> | .-1-----. | '-SYSPLEXPorts-' '-OPTLOCAL--+-------+-' '-value-' .-TIMEDAFFinity 0-------. >--+-----------------------+------------------------------------| '-TIMEDAFFinity seconds-' Tier1 Parameters |--| Tier1 Options |--+-ipv4_addr-----+-------------------------> '-ipv6_intfname-' >--+-----------------------+------------------------------------> | .-------------. | | V | | '-PORT----+-num-----+-+-' '-num-num-' >--DESTIP--+-ALL-------------------------------------------------+--| | .-------------------------------------------------. | | V | | '---targetip--+-----------------------------------+-+-' +-| DESTIP WEIGHTEDACTIVE options |-+ '-| DESTIP HOTSTANDBY options |-----' Tier1 Options (These can be specified in any order) .-DEFINE-. |--+--------+---------------------------------------------------> '-DELEte-' .-DISTMethod BASEWLM -| BASEWLM distribution method options |------------. >--+-+------------------------------------------------------------------------+-+--> | '-DISTMethod--+-ROUNDROBIN---------------------------------------------+-' | | +-SERVERWLM -| SERVERWLM distribution method options |---+ | | +-WEIGHTEDActive-----------------------------------------+ | | '-HOTSTANDBY -| HOTSTANDBY distribution method options |-' | | .-DISTMethod ROUNDROBIN----------. .-CONTROLPORT 1702--------. | '-+-GRE---+--+--------------------------------+--+-------------------------+-' '-ENCAP-' '-DISTMethod--+-WEIGHTEDActive-+-' '-CONTROLPORT port_number-' '-TARGCONTRolled-' .-NOOPTLOCAL----------. >--+---------------------+--+--------------+--------------------> | .-1-----. | '-SYSPLEXPorts-' '-OPTLOCAL--+-------+-' '-value-' >--+-TIMEDAFFinity 0-------+--TIER1--groupname------------------| '-TIMEDAFFinity seconds-' Tier2 Parameters |--| Tier2 Options |--+-ipv4_addr-----+-------------------------> '-ipv6_intfname-' >--+-----------------------+------------------------------------> | .-------------. | | V | | '-PORT----+-num-----+-+-' '-num-num-' >--DESTIP--+-ALL-------------------------------------------------+--| | .-------------------------------------------------. | | V | | '---dynxcfip--+-----------------------------------+-+-' +-| DESTIP WEIGHTEDACTIVE options |-+ '-| DESTIP HOTSTANDBY options |-----' Tier2 Options (These can be specified in any order) .-DEFINE-. |--+--------+---------------------------------------------------> '-DELEte-' .-DISTMethod BASEWLM-| BASEWLM distribution method options |-------------. >--+------------------------------------------------------------------------+--> '-DISTMethod--+-ROUNDROBIN---------------------------------------------+-' +-SERVERWLM -| SERVERWLM distribution method options |---+ +-WEIGHTEDActive-----------------------------------------+ '-HOTSTANDBY -| HOTSTANDBY distribution method options |-' .-NOOPTLOCAL----------. >--+---------------------+--+--------------+--------------------> | .-1-----. | '-SYSPLEXPorts-' '-OPTLOCAL--+-------+-' '-value-' .-TIMEDAFFinity 0-------. >--+-----------------------+--TIER2--groupname------------------| '-TIMEDAFFinity seconds-' DESTIP WEIGHTEDACTIVE options .-WEIGHT 10----. |--+--------------+---------------------------------------------| '-WEIGHT value-' DESTIP HOTSTANDBY options |--+-PREFERRED--------+-----------------------------------------| | .-1----. | '-BACKUP--+------+-' '-rank-' BASEWLM distribution method options .-PROCTYPE CP 1 ZAAP 0 ZIIP 0-. |--+------------------------------+-----------------------------| | .----------------. | | V .-CP 1-. | | '-PROCTYPE----+-+------+---+-+-' | '-CP x-' | | .-ZAAP 0-. | +-+--------+-+ | '-ZAAP y-' | | .-ZIIP 0-. | '-+--------+-' '-ZIIP z-' SERVERWLM distribution method options .-PROCXCOST--ZAAP 1 ZIIP 1------. .-ILWEIGHTING 0------. |--+-------------------------------+--+--------------------+----| | .----------------. | '-ILWEIGHTING--+-1-+-' | V .-ZAAP 1-. | | +-2-+ '-PROCXCOST----+-+--------+-+-+-' '-3-' | '-ZAAP x-' | | .-ZIIP 1-. | '-+--------+-' '-ZIIP y-' HOTSTANDBY distribution method options .-AUTOSWITCHBACK---. .-HEALTHSWITCH---. |--+------------------+--+----------------+---------------------| '-NOAUTOSWITCHBACK-' '-NOHEALTHSWITCH-'
Restriction: You cannot specify DISTMETHOD BASEWLM if you specify GRE or ENCAP.
Rule: You must specify IPCONFIG SYSPLEXROUTING on all target systems to use this distribution method.
BASEWLM distribution method options:
For applications that use specialty processors and receive WLM system weight recommendations, specify a PROCTYPE parameter to indicate the expected proportion of each type of processor that the target application's workloads should use. A composite recommendation is determined from these proportions. Each of the proportions should be expressed as a number in the range 0 - 99. Each proportion value is divided by the total to determine the processor usage pattern. To determine the processor proportions to configure, study your workload usage of assist processors by analyzing SMF records, using performance monitors reports, such as RMF™, and so on.
For example, the value PROCTYPE CP 5 ZAAP 0 ZIIP 3 specifies a processor usage pattern such that 5/8 of the application's CPU utilization uses conventional processors (CP), and 3/8 of the application's CPU utilization uses zIIP processors.
For example, the value PROCTYPE CP 60 ZAAP 30 ZIIP 10, would specify a processor usage pattern such that 60% uses conventional processors (CP), 30% uses zAAP processors, and 10% uses zIIP processors.
The value PROCTYPE CP 1 ZAAP 0 ZIIP 0 is the default value; this value is used when the PROCTYPE parameter has never been specified. The default value indicates that 100% of the conventional processor weight (CP) should be considered when determining the composite weight (the application's workload does not use zIIP or zAAP processors). This value also disables an existing PROCTYPE value.
Specifying the PROCTYPE parameter without any parameters is equivalent to specifying the default values; you can use this setting disable an existing PROCTYPE value.
Restriction: When processor types are specified, at least one type must be specified with a nonzero value.
Result: If a distribution target has a Target Server Responsiveness (TSR) value of 0, it is normally not used as a target for distribution. For more information about responsiveness monitoring, see z/OS Communications Server: IP Configuration Guide.
Rule: You must specify IPCONFIG SYSPLEXROUTING on all target systems to use this distribution method.
Result: zAAP and zIIP processor capacity is automatically included when SERVERWLM is specified and all systems in the sysplex are V1R9 or later.
Restriction: You cannot specify SERVERWLM if you specify GRE or ENCAP.
Port sharing
Specifying SHAREPORT on the PORT statement in the TCP/IP profile enables a group of servers to listen on the same port and thereby share the incoming workload. As new connections are received, the SHAREPORT algorithm distributes connections in a weighted round-robin fashion based on each server's Server accept Efficiency Fraction (SEF). By specifying SHAREPORTWLM on the PORT statement, connections are distributed in a weighted round-robin fashion based on the WLM server-specific recommendations, as modified by the Server accept Efficiency Fraction (SEF). If the shared port is a sysplex-distributed port and SERVERWLM is the distribution method that is being used, then SHAREPORTWLM should be coded on each target's PORT statement to take advantage of the new WLM server-specific recommendations when connections are received at the target; if it is not, new connections continue to be distributed using the existing SHAREPORT algorithm when they are received at the target.
Result: zAAP and zIIP processor capacity is automatically included when SHAREPORTWLM is specified and all systems in the sysplex are V1R9 or later.
SERVERWLM distribution method options:
The ILWEIGHTING parameter specifies the weighting factor that WLM uses when comparing displaceable capacity at different importance levels (ILs) as it determines a SERVERWLM recommendation for each system. The parameter value indicates how aggressively WLM should favor systems with displaceable capacity at low importance levels over systems with displaceable capacity at high importance levels. The higher the value specified for ILWEIGHTING the more a stack with displaceable capacity at lower importance levels is favored. See the internal load balancing information in z/OS Communications Server: IP Configuration Guide for more information about the effects of this parameter.
Guideline: If you specify any value other than the default value (0), for the first time, specify this value (1) initially.
zAAPs and zIIPs are specialty processors designed to off-load specific application workloads. Some target applications are designed to have a portion of their workload take advantage of these processors.
For server-specific recommendations, WLM calculates a composite weight based on a comparison, for each system, of the available capacity of each processor modified by the proportion of processor usage by the application. However, the composite weight does not consider that the conventional processor proportion on a system might be higher than normal because specialty processing capacity is constrained; a portion of the workload intended to run on a specialty processor ran on the conventional processor instead.
This parameter specifies a crossover cost which is applied to the zAAP or zIIP targeted workload that ran on the conventional processor; it reduces the conventional processor proportion which in turn reduces the composite weight for that system. This parameter can be used to cause WLM to favor systems that had less crossover (more of their workload running on the intended specialty processor) over systems that had more crossover. The higher the PROCXCOST crossover value, the more aggressively WLM recommendations favor systems with more specialty engine capacity which can reduce overall processing cost; however, if you use a PROCXCOST value that is too aggressive (high), overall workload performance for that service class might be sacrificed. The RMF Workload Activity Report shows the zAAP and zIIP processor utilization as well as how much crossover took place. Run this report before, and after, using the PROCXCOST parameter to better understand how this affects your overall workload performance.
You can specify the weight for each target on the DESTIP parameter after each target's IP address. If you configure the value DESTIP ALL, then the default weight 10 is used and the connection distribution goal is to have an equal number of active connections for each DESTIP target. For more information, see the DESTIP WEIGHTEDACTIVE options.
This distribution method is not influenced by the number of server instances that are active on a target TCP/IP stack instance and listening on the same port (SHAREPORT parameter specified on the PORT reservation statement). For example, when two target TCP/IP stacks are configured with the same active connection weight, if one of the targets has multiple active servers for that port and the other target has only one instance of that server active, both stacks initially receive the same number of connection requests.
Rule: You must specify IPCONFIG SYSPLEXROUTING on all target systems to use this distribution method.
The target to which connections are distributed is referred to as the active target. If AUTOSWITCHBACK is configured, then the preferred target is the active target if it is available and has not had any health problems. If the active target becomes unavailable, the hot-standby target becomes the new active target, and the unavailable target becomes a hot-standby target.
A target is unavailable if any of the following conditions are true:
Requirement: PREFERRED or BACKUP must be configured on the DESTIP parameter for each target after the dynamic XCF address. For more information, see the DESTIP HOTSTANDBY options.
Rule: IPCONFIG SYSPLEXROUTING must be specified on all target systems for this distribution method to be used.
Result: In the Netstat VDPT/-O report, ACTIVE is displayed if this is currently the active target, and BACKUP is displayed if this is currently a hot-standby target. For more information about the Netstat VDPT/-O report, see z/OS Communications Server: IP System Administrator's Commands.
HOTSTANDBY distribution method options:
Automatic switchback does not occur if the preferred target initially became unavailable because it was not healthy (TSR, WLM abnormal terminations, WLM health). A standby target that had health problems while active can look healthy again because it is not processing new work.
SYSPLEXPORTS must be specified on the first VIPADISTRIBUTE statement for a DVIPA. It cannot be enabled after a DVIPA has been marked for distribution. If enabled, it cannot be disabled until all distribution has been deleted for the DVIPA (except for quiescing the DVIPA on the target stacks).
If you send connection requests to SYPLEXPORTS-enabled distributed DVIPAs and a random ephemeral port with no associated listener, then this connection times out.
The groupname value specifies the name of a cluster of equivalent server applications in the sysplex that the tier 1 targets might distribute the requests to. The groupname value can be 1 - 16 characters in length, must begin with an alphabetic character, and must not contain any national symbols, including @ or $. This value is used to correlate this statement with a corresponding TIER2 VIPADISTRIBUTE statement or statements. When TIER1 is specified, groupname is required, even if TIER2 definitions are not used.
GRE | Inner IP header | ||
---|---|---|---|
Source IP | Dest IP | Source IP | Dest IP |
XCF@ | DataPower IP@ | Distributed DVIPA1 | Distributed DVIPA1 |
After the GRE header is stripped away at the DataPower appliance, the connect() call will hang because the DataPower routing logic assumes that the packet should remain local because the source IP address (DVIPA1) is locally defined on the appliance as a non-advertised IP address.
The source IP address must be routable by the DataPower appliance. You can use the SRCIP statement to select an appropriate source IP address for the client application.
For more information about source IP selection, see z/OS Communications Server: IP Configuration Guide. For more information about the SRCIP statement, see SRCIP statement.
Tip: If you specify GRE, a control connection to the Tier 1 target is always established, using the CONTROLPORT port number as the destination port.
OuterIP header | Inner IP header | ||
---|---|---|---|
Source IP | Dest IP | Source IP | Dest IP |
XCF@ | DataPower IP@ | Distributed DVIPA1 | Distributed DVIPA1 |
After the outer IP header is stripped away at the DataPower appliance, the connect() call will hang because the DataPower routing logic assumes that the packet should remain local because the source IP address (DVIPA1) is locally defined on the appliance as a non-advertised IP address.
The source IP address must be routable by the DataPower appliance. You can use the SRCIP statement to select an appropriate source IP address for the client application.
For more information about source IP selection, see z/OS Communications Server: IP Configuration Guide. For more information about the SRCIP statement, see SRCIP statement.
Tip: If you specify ENCAP, a control connection to the Tier 1 target is always established, using the CONTROLPORT port number as the destination port.
The groupname value specifies the name of a cluster of equivalent server applications in the sysplex that the Tier 1 targets might distribute the requests to. It is used to correlate this statement with a corresponding TIER1 VIPADISTRIBUTE statement.
The groupname value can be 1 - 16 characters in length, must begin with an alphabetic character, and must not contain any national symbols, including @ or $.
Restriction: Under some circumstances, a client's affinity with a specific target application server instance might be terminated prior to the specified time interval. This can occur if the key resources needed to satisfy new client TCP connection requests are not available. See z/OS Communications Server: IP Configuration Guide for more information.
If the TIMEDAFFINITY parameter is not initially specified on a VIPADISTRIBUTE statement, this indicates that timed affinity is not being used for the distributed DVIPA and ports, which is the same as specifying TIMEDAFFINITY 0.
Restriction: The TIMEDAFFINITY parameter cannot be specified with the OPTLOCAL keyword.
A value of 0 indicates that connections originating from a target stack within the sysplex should always bypass sending the connection request to the sysplex distributor. The relative capacities of other target stacks within the sysplex are not considered in determining whether the connection should remain local.
A value of 1 indicates that connections originating from a target stack within the sysplex should always bypass sending the connection request to the sysplex distributor as long as the WLM weight for the server on the local stack is not 0. This is the default value if OPTLOCAL is specified without a value.
If a value in the range 2 - 16 is specified, the value is used as a multiplier against the local target stack's raw WLM weight to cause it to be favored over the other target stacks. The relative capacities of the other target stacks within the sysplex are considered in determining which stack should process the connection. The higher the value specified, the more the local stack is favored over other target stacks.
Regardless of the value specified on the OPTLOCAL parameter, if no local server is available, or the SEF is less than 75 or the abnormal transaction completions is greater than 250, or the health indicator is less than 75, connections are sent to the distributing stack.
Result: If the configured distribution method is ROUNDROBIN, WEIGHTEDACTIVE, or HOTSTANDBY, the OPTLOCAL value is forced to 0.
Rule: An IPv4 address is not allowed if TIER1 ENCAP is specified.
Rule: An IPv6 interface is not allowed if TIER1 GRE is specified.
If the PORT parameter is specified, servers that bind to the specified DVIPA, the IPv4 INADDR_ANY address, or to the IPv6 unspecified address (in6addr_any) and one of the specified ports, cause the target stack to become eligible to receive connection requests.
Requirement: If you specify TIER1 GRE or TIER1 ENCAP, you must specify the PORT parameter.
A maximum of 32 destination (target) dynamic XCF addresses can be specified.
When you specify TIER1 without specifying GRE or ENCAP, this parameter specifies the dynamic XCF address (IPCONFIG DYNAMICXCF) of the TCP/IP stacks in the sysplex that are to be target stacks for the dynamic VIPA. The target stacks are candidates to receive new incoming connection requests.
A maximum of 32 Tier 1 target IP addresses can be specified.
Requirement: You must specify TIER1 and either GRE or ENCAP when specifying the IP address of a non-z/OS host.
DESTIP WEIGHTEDACTIVE options:
This parameter is configured following a DESTIP targetip or dynxcfip value.
This parameter has meaning only if the distribution method is WEIGHTEDACTIVE; it is ignored if this is not the distribution method. The weight is used by the distributor to determine the proportion of incoming requests to route to this target such that the number of active connections on each target is proportionally equivalent to the configured weight for each target. Valid values are in the range 1 - 99.
For example, if target 1 has a weight of 10 and target 2 has a weight of 90, then the connection distribution goal is to have 9 times as many active connections on target 2 as on target 1, or 10% of the active connections on target 1 and 90% of the active connections on target 2. If a weight is not specified, the default value of 10 is used. If the distribution method is WEIGHTEDACTIVE and weights are not configured for any targets, the goal is to have an equal number of active connections on each target.
Guidelines: Although weights can be in the range 1- 99, it is preferred to use weights that are greater or equal to 10. This is because the target server health metrics (Target Server Responsiveness [TSR] fractions) abnormal terminations, and the health indicator fractions are used to reduce the weight when these values are not optimal. By specifying weights greater than or equal to 10, these metrics can be applied without losing the original weight distinctions between targets. For example, if target 1 has a weight of 2, target 2 has a weight of 1, and a TSR for target 1 of 90% is applied, target 1 has a reduced weight of 1 (equal to target 2), but if target 1 has a weight of 20 and target 2 has a weight of 10, then when the TSR of 90% is applied to target 1, it has a weight of 18 (weight reduced, but it is still preferred over target 2).
If your workload has a low connection arrival rate (less than 100 connections per minute), and typically has a low number of active connections (less than 1000 active connections), you will get the most accurate distribution if you configure each weight so that it is a multiple of 10.
DESTIP HOTSTANDBY options:
Specify this parameter after the dynamic XCF address (dynxcfip) on the DESTIP parameter. This parameter specifies that this address is the preferred target when the distribution method is HOTSTANDBY. If you configure AUTOSWITCHBACK, then the preferred target is the active target if it is available and has not had any health problems. If the active target becomes unavailable, the distributor switches to use a hot-standby target; the active target becomes a hot-standby target and the selected hot-standby target becomes the active target.
Restriction: You can specify this parameter only if you specify DISTMethod HOTSTANDBY.
Specify this parameter after the dynamic XCF address (dynxcfip) on the DESTIP parameter. This parameter specifies that this address is one of the backup targets when the distribution method is HOTSTANDBY.
The rank is used to determine which backup target is selected if the preferred target becomes unavailable. The backup with the highest rank is used. Valid values for rank are in the range 1 - 254; the default value is 1.
Restriction: You can specify this parameter only if you specify DISTMethod HOTSTANDBY.
VIPADISTRIBUTE DELETE ipaddr PORT port_num ... DESTIP dynxcfip ...
VIPADISTRIBUTE DELETE ipaddr PORT port_num DESTIP ALL
VIPADISTRIBUTE DELETE ipv6_intfname PORT port_num ... DESTIP dynxcfip
VIPADISTRIBUTE DELETE ipv6_intfname PORT port_num DESTIP ALL
VIPADEFINE 255.255.255.192 9.67.240.02
VIPADISTRIBUTE
DISTMETHOD SERVERWLM 9.67.240.02 PORT 10000 DESTIP ALL
VIPADEFINE TIER2 CPCSCOPE V6DVIPA1 2000::9:67:240:2/96
VIPADISTRIBUTE
DISTMETHOD SERVERWLM PROCXCOST ZIIP 2 ZAAP 2 ILWEIGHTING 2
TIER2 LOCALGROUP OPTLOCAL 1 SYSPLEXPORTS
V6DVIPA1 PORT 10000 DESTIP ALL