VARY TCPIP,,PURGECACHE

Use the VARY TCPIP,,PURGECACHE command to delete the ARP cache entries or neighbor cache entries for an interface.

Parent topic: VARY command: TCP/IP address space

Format

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>>-Vary --TCPIP--,--+----------+--,--PURGECache,name-----------><
                    '-procname-'                       

Parameters

name
The interface name of the cache that is to be purged.
If the name value matches an IPv4 interface name, the local ARP cache or the outboard OSA cache entries (for QDIO token ring and QDIO Ethernet) for that interface is purged. If the name matches an IPv6 interface name, the IPv6 neighbor cache for that interface is purged.
Note:
  1. Purging of the OSA outboard cache entries requires a level of microcode that supports the Flush ARP table ARP Assist Option Request. When this command is issued against an IPv4 QDIO token ring or Ethernet interface and the OSA-Express device is shared by multiple stacks, then this command purges the ARP cache for all stacks that share the OSA (because an OSA-Express device maintains a single ARP cache for all stacks that share it).
  2. Translate entries are not deleted for ATM or LCS interfaces.

    For ATM, the following conditions apply:

    • PVC and ATMARP server entries are not deleted.
    • ACTIVE SVC entries are not deleted because TCP/IP processing periodically validates these entries.
    • A clear might be needed for SVC entries that are not ACTIVE. When the asynchronous clear completes, the entries are deleted.

Examples

The following example shows how to use PURGECache.

  • From TSO: 
     netstat arp all 
MVS TCP/IP NETSTAT CS V1R9 TCPIP Name: TCPCS 
 Querying ARP cache for address 9.67.113.1 
 Interface: TR1 IBMTR: 000BC6AA1B88 
 Route info: 0000

 Querying ARP cache for address 9.67.113.61 
 Interface: TR1 IBMTR: 08005A8B2EC7 
 Route info: 02A0 
 READY
  • On MVS™ console: 
     v tcpip,,purgec,tr1 
 PROCESSING COMMAND: VARY TCPIP,,PURGEC,TR1
 COMMAND PURGECACHE COMPLETED SUCCESSFULLY 
 PURGECACHE PROCESSED FOR LINK TR1
  • From TSO: 
       netstat arp all 
 MVS TCP/IP NETSTAT CS V1R9 TCPIP Name: TCPCS 
 Querying ARP cache for address 9.67.113.61 
 Interface: TR1 IBMTR: 08005A8B2EC7
 Route info: 02A0
 READY

Usage

Users can be authorized to invoke the command by permitting their user IDs for CONTROL access to the RACF® profile name MVS.VARY.TCPIP.PURGECACHE.