VIPADYNAMIC - VIPADEFINE statement

Parameters

TIER1

Indicates that the dynamic VIPA whose address is specified as an IP address on this statement are used to distribute incoming requests to z/OS® or non-z/OS targets (for example, DataPower® appliances).

Restriction: You cannot configure this parameter on this statement if TIER2 is configured. A dynamic VIPA address cannot be used as both a TIER1 and TIER2 address.

TIER2

Indicates that the dynamic VIPA whose address is specified as an IP address on this statement are used to distribute incoming requests from Tier 1 targets to the group of server applications that is named.

Restriction: You cannot configure this parameter on this statement if TIER1 is configured. A dynamic VIPA address cannot be used as both a TIER1 and TIER2 address.

CPCSCOPE

Indicates that the dynamic VIPA whose address is specified as an IP address on this statement is specific to the central processor complex (CPC) on which it is defined. That is, it is not moved to, or taken over, by another TCP/IP stack that is in a different CPC.

Tier 1 non-z/OS target addresses must be on the same subnet as the subnet determined by the address_mask or prefix_len value.

Restrictions:

• A DVIPA defined with the CPCSCOPE parameter cannot be used in a VIPADISTRIBUTE DEFINE statement unless TIER2 is also configured .
• You cannot configure this parameter on this statement if TIER1 is configured.

MOVEABLE

This parameter is used to specify when a DVIPA that has been activated on this TCP/IP stack can be moved to another TCP/IP stack when the other TCP/IP stack requests ownership.

Rule: To preserve connections during dynamic VIPA takeover, you must specify the DYNAMICXCF parameter on the IPCONFIG statement for IPv4 DVIPA interfaces and on the IPCONFIG6 statement for IPv6 DVIPA interfaces.

IMMEDIATE

Specifies an immediate nondisruptive movement of a dynamic VIPA from one stack to another stack. This indicates that this dynamic VIPA can be moved to another stack as soon as the other stack requests ownership of the VIPA by executing a VIPADEFINE statement for the same dynamic VIPA. The new owning stack forwards packets for any existing connections to the original stack in order that the existing connections are not disturbed. All new connection requests are directed to the new owning stack. This is the default value.

The IMMEDIATE option is the only option supported for IPv6 addresses.

WHENIDLE

Indicates that this dynamic VIPA can be moved to another stack when there are no connections for this DVIPA on the current stack. While there are existing connections, any new connection requests continue to be directed to the current stack.

This option is not supported for IPv6.

SERVICEMGR

Indicates that sysplex distributor performs Multinode Load Balancing (MNLB) by functioning as a Service Manager (in place of Cisco's LocalDirector) for these distributed dynamic VIPAs. SERVICEMGR has no effect if a VIPADISTRIBUTE DEFINE statement does not exist for this VIPA.

Restrictions:

• MNLB is not supported for IPv6 DVIPAs; the SERVICEMGR parameter is ignored for these types of addresses.
• The SERVICEMGR parameter is ignored when TIER1, TIER2, or CPCSCOPE is specified.

address_mask

Specifies the subnet mask that determines how many of the bits of the IP address determine the subnet. All IP addresses in the same VIPADEFINE statement list must belong to the same subnet. That is, if the address_mask value is logically ANDed with all the IP addresses in the list, the resulting values must all be the same. The first IP address in the list determines the subnet.

When you specify the subnet mask for a DVIPA with a value of CPCSCOPE, ensure that the subnet is the same subnet that is used for tier 1 non-z/OS targets, such as DataPower appliances, that are routing requests to tier 2 targets on this CPC.

The address_mask value is specified in standard dotted decimal format; the IP addresses in the subnet must be a single contiguous range of IP addresses. A subnet mask of 0.0.0.0 is not valid.

Rules: The address_mask value must meet the following normal mask definition rules:

• When converted to binary, the most significant bit must be 1.
• When converted to binary, all bits less significant than (to the right of) the first 0 encountered must also be 0.

Restriction: This parameter applies only to IPv4 addresses.

ipv4_addr

Specifies the specific DVIPA to be defined. More than one ipv4_addr value can be specified on a single VIPADEFINE statement. A mixture of IPv4 addresses and an IPv6 interface on the same VIPADEFINE statement is not permitted. A mixture of VIPADEFINE statements with all IPv4 addresses and VIPADEFINE statements with IPv6 addresses is permitted within the same VIPADYNAMIC/ENDVIPADYNAMIC block, and the VIPADEFINE statements can be intermixed in any order.

If a DVIPA in this VIPADEFINE statement list is already active on another stack as a dynamic VIPA that was activated by VIPADEFINE or VIPABACKUP statement, the result of this VIPADEFINE statement depends on the level of each stack and how the DVIPA was originally defined.

If the DVIPA was originally defined with MOVE IMMEDIATE, then the original owning stack immediately gives up ownership of the DVIPA and the DVIPA is activated on this stack. If there were any connections to the DVIPA on the original owning stack, the newly owning stack forwards packets to the original stack in order that the existing connections are not disturbed.

If two or more stacks in the sysplex have the same DVIPA in VIPADYNAMIC VIPADEFINE statements, with different address masks, the stack that gets the active DVIPA determines the address mask.

If a DVIPA in this VIPADEFINE statement list is already active on this stack or another stack either as an IP address in a HOME statement or as a dynamic VIPA activated by way of an IOCTL or a BIND implicit activation, the DVIPA in the VIPADEFINE statement list is rejected and an error message is issued.

ipv6_intfname

The name of the interface. The maximum length is 16 characters. This specified name and the address specified in ipv6_addr are verified to ensure that the DVIPA interface is uniquely (consistently) defined throughout the sysplex environment.

ipv6_addr

Specifies the specific DVIPA to be defined. Only one ipv6_addr value can be specified on a single VIPADEFINE statement. A mixture of IPv4 addresses and IPv6 interfaces on the same VIPADEFINE statements is not permitted. A mixture of VIPADEFINE statements with all IPv4 addresses and VIPADEFINE statements with an IPv6 address is permitted within the same VIPADYNAMIC/ENDVIPADYNAMIC block, and the VIPADEFINE statements can be intermixed in any order.

If theDVIPA specified by the ipv6_addr value is already active on another stack as a dynamic VIPA that was activated by the VIPADEFINE or VIPABACKUP statement on the same interface name, the DVIPA is activated on this stack and changed to backup status on the other stack.

Requirement: All stacks (distributing stack, backup stack, target stack) which participate in distribution for a distributed DVIPA with IPv6 address must be at least z/OS V1R6.

If the specified ipv6_addr is already active on this stack or another stack either as an IP address on an INTERFACE statement or as a dynamic VIPA activated by way of an IOCTL or a BIND implicit activation, the VIPADEFINE statement is rejected and an error message is issued.

See Restrictions on IPv6 addresses configured in the TCP/IP profile for a description of the ipaddr_spec parameter and a list of restrictions that must be observed when specifying this parameter.

/prefix_len

Specifies the prefix length to be used when calculating a prefix for CPCSCOPE processing. The number of bits in the ipv6_addr value defines the prefix. Valid values are in the range 1 - 128.

When you specify the prefix length for a CPCSCOPE DVIPA, ensure that the prefix is the same subnet that is used for the tier 1 targets that are in this CPC.

Restriction: This parameter applies to IPv6 only.

Steps for modifying

• To remove one or more of the IPv4 addresses, use:

  VIPADELETE  ipv4_addr  [ipv4_addr ...]
   

• To remove an IPv6 DVIPA interface, use:

  VIPADELETE ipv6_intfname

  If the IPv4 DVIPA address or IPv6 DVIPA interface is being distributed, you must use one or more VIPADISTRIBUTE DELETE statements to end distribution before you can use the VIPADELETE statement to delete the DVIPA. The VIPADISTRIBUTE DELETE and VIPADELETE statements can appear in the same VARY TCPIP,,OBEYFILE command data set.
• To change the mask for one or more of the IPv4 addresses, you must first delete the IP addresses and then redefine them with the new mask:

  VIPADELETE  ipv4_addr  [ipv4_addr ...]
  VIPADEFINE  new_mask  ipv4_addr  [ipv4_addr ...]

  If the IP address is active, the VIPADELETE statement breaks any existing connections and causes the dynamic VIPA to be activated elsewhere in the sysplex if there is another stack prepared to activate it.
• To change the SERVICEMGR setting, you must first delete the DVIPA and then redefine it with the SERVICEMGR setting that you want.
• To change a VIPADEFINE from TIER1 to TIER2, from TIER2 to TIER1, from non-TIER to TIER, or from TIER to non-TIER, you must first specify a VIPADELETE ipaddr value.