Attempting to Read, Forward, or Reply in Webaccess causes a blank white screen to show for 2 to 4 minutes before displaying content

  • 7014792
  • 25-Mar-2014
  • 25-Mar-2014

Environment

Novell GroupWise 8 Support Pack 3 Hot Patch 1
Novell GroupWise 2012 Support Pack 2
SUSE Linux Enterprise Server 11 Service Pack 2 (SLES 11 SP2)

Situation

Suddenly for no apparent reason, when any GroupWise user on any workstation in any internet browser logs into Webaccess and attempts to READ or FORWARD a message or REPLY to a message, the resulting window or screen that should show the content of the message would take from 2 to 4 minutes to actually show any data.

Resolution

It was discovered after much troubleshooting and taking and reading network packet traces, that IPv6 being enabled was the cause of the issue.  Once this was disabled and this issue was monitored for over 2 weeks , the issue never returned.

To check if you have IPv6 running on the server , you can also go to a Linux terminal and issue the command "ifconfig", if you see "inet6" anywhere then that is a good sign you have it running.

Also if you run this command at a Linux terminal "lsmod | grep | -i "ipv6" and if you see something like this as a result, then you do not have IPv6 enabled :  "ipv6_lib                                345070   0"

One way to disable IPv6 on SLES11, go to Computer | Yast | Network Devices | Network Settings | Global Options tab | IPv6 Protocol Settings, uncheck "Enable IPv6", Click OK and exit YAST.  At your first opportunity Restart the SLES11 server.

Cause

Somehow by having IPv6 enabled, port 0 (zero) was open and in a listen state and somehow a denial of service attack was conducted on the Webaccess Linux server thru this port, causing the high latency.  Once IPv6 was disabled, port 0 was no longer in a listen state and was not available for use.

Feedback service temporarily unavailable. For content questions or problems, please contact Support.