db2

A case of bad network configuration file

DB2 works just great on any platform and it has becoming a lot more better with every release.  This has nothing to do with this post !  Just wanted to say that !  Recently one of my novice system admin was configuring a DB2/AIX server and somehow screwed up the IPv6 configuration.  This caused db2 commands to appear to hang and  responded extremely slow.  DB2 commands returned the following message:

DB21015E The Command Line Processor backend process request queue or input
queue was not created within the timeout period.

Starting with DB2 V9.1 when DB2 calls AIX with getaddrinfo(), it will ask for both an IPv4 and an IPv6 address.  When the server  does not have IPv6 configured, it is time consuming for AIX to attempt to get an IPv6 address before it fails. The AIX resolver will first get the address locally, then if that fails, it will go to the DNS server. Since DB2 relies on AIX for getting address information, this cause DB2 commands to appear to be hanging.

Inorder forAIX resolver to return both IPv4 and IPv6 address, ensure the /etc/netsvc.conf file has the entry :
hosts=local,bind

For servers that do not have IPv6 configured, you should configure the/etc/netsvc.conf file as follows:
hosts=local4,bind4