IBM PowerHA(HACMP) shutdowns oracle 11.2 because of IPv6 and DNS is not accessable


Just a quick post with some additions to situation covered in

Investigation of the 11g Oracle*Net connection delay when DNS server is unreachable.

Just a short recap:

  • customer experienced long timeout(slow connection) doing tnsping to 11.2 database running on AIX when DNS server was unreachable;


TNS Ping Utility for IBM/AIX RISC System/6000: Version – Production

Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = dns-hostname)(PORT = 1521))   (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = XXX)))

OK (150010 msec)

  • issue was because of IPv6 support was included in Oracle 11g and even if connection hostname was resolved by /etc/hosts to IPv4 client tried to resolve it to IPv6 address too.
  • issue was fixed by replacing local, bind by local4, bind4  in the /etc/netsvc.conf.

So why I’m doing this recap ?

It’s because of mentioned problem was only a part of issue faced during IBM PowerHA(HACMP) cluster with oracle resources testing. Continue reading


Intermittent Slow Oracle Net from Windows 7/Vista/2008 machines


I have faces some interesting issue that worth a blog post.

After rebooting Windows 2003 Server with installed Oracle Database 9.2 some clients machines(with installed Windows 7) started to work very slowly with Oracle Database. Other clients, with installed Windows XP, worked as usual – fine. There no network hardware issues for Windows 7 machines – both machines were tested for the same network cable: Windows XP works fine, but Windows 7 is very slow…

Oracle sessions were tracing with 10046(level 12) event and it revealed that there are no issues with database – just network…

Listener was rebooted – didn’t helped…

System administrators noticed that Windows 2003 machine was claiming that it was not able to update root certificates, so they decided to provide Internet connection and update root certificates. Updates required server reboot and… vuala… after server rebooted everything was OK from every workstation.

Nobody was able to explain what was THE REASON, but EVERYBODY  WERE HAPPY.

Later, in two days, they required to reboot mentioned server once again, and after reboot Windows 7 workstation started working slowly…

I was there so it was time to see what is happening. Continue reading