FYI - I chased this down via a support case, because I was concerned that this information was so difficult to find and I believe this kind of information should have been more easily available to us(?)
The below issue is referenced in:
Short summary;: There is risk of corruption in SyBase (EMM and OpsCenter although note only mentions OpsCenter) on RHEL. Issue is between SyBase and RHEL Transparent HugePage features. It is not currently known to support whether issue is fixed in RHEL 6.4/6.5, but no matter what, it requires a fix in SyBase as well, which MAY be included in 18.104.22.168.
Until then, here is the workaround to disable THP in RHEL:
RHEL 6.x: /etc/sysctl.conf #Disable Transparent Huge Pages - Symantec TECH218263 transparent_hugepage = never redhat_transparent_hugepage = never
Reboot and confirm:
# cat /sys/kernel/mm/redhat_transparent_hugepage/enabled
# cat /sys/kernel/mm/transparent_hugepage/enabled
On the fly:
echo never > /sys/kernel/mm/transparent_hugepage/enabled
echo never > /sys/kernel/mm/redhat_transparent_hugepage/enabled
This is NOT mentioned in either SORT or compatibility matrix :-(
From: Enterprise Technical Support [mailto:firstname.lastname@example.org]
Sent: 25. juni 2014 03:42
To: Morten Seeberg
Subject: RE: Case: 06402450
As discussed the messages regarding THP come from the Sybase database service because it believes it detects an operating system bug, so it is not something Symantec has direct control over.
If Sybase believes that it detects the situation, it automatically generates those messages and disables direct I/O. If our customer has updated their RedHat patches to a version that RedHat considers fixed but the messages still happen when THP is enabled, then RedHat needs to work with SAP, the company that sells Sybase, because Sybase believes it is not fixed.
About the EMM database of Master server?
Yes, EMM is also effected in the same way. We verified it on RedHat 6.3 lab system.
The technote will be updated soon.
If the customer has updated their operating but still needs this issue addressed, they have several choices:
1. Work with RedHat to engage SAP. The customer should be sure to provide them the information "RedHat bug 891857 and Sybase Build #3840-Engineering Case #728734".
2. Wait until 22.214.171.124 comes out and then upgrade to it, then re-enable THP (after backing up the database of course) to see if the issue still exists. OpsCenter/NetBackup 126.96.36.199 is planned to have a newer build Sybase update patch included.
3. Contact BCAM(Business Critical Account Manager) to arrange for the customer to work directly with the product managers in charge of OpsCenter and EMM portion of NetBackup. The product managers have control over NetBackup/OpsCenter development. The customer should be sure to mention that this is RedHat bug 891857 and Sybase Build #3840-Engineering Case #728734.