I have a problem with a slow data stream when running a Netbackup Media Server 18.104.22.168 on RedHat 5.8. We are migrating systems from Solaris 10 to RedHat 5.8. The speed on Solaris 10 is about twice as fast as the RedHat 5.8 system. Also, we have no problem with earlier versions of RedHat, just 5.8. I was told that the 5.8 version is a different animal than even RedHat 5.6. Is there a different OS config I need to set up to get RedHat 5.8 and Netbackup 7.5 to get along? Possibly buffer changes, kernel tweaks, etc?
1: check SIZE_DATA_BUFFERS & NUMBER_DATA_BUFFERS in Netbackup
2: Check NIC is working as intended. Use the Netbackup GEN_DATA directive to verify path can transfer data. http://www.symantec.com/docs/TECH75213
Am using RH 5.8 and has no problem in trasfering >300MB/sec via 10GB ethernet
There are special buffer for FTL configurations (NUMBER_DATA_BUFFERS_FT & SIZE_DATA_BUFFERS_FT ) . Do you got those set ?
The "FT" buffers wouldn't apply in my case since I'm not using Fiber Transport, but I will double check the standard I/O buffer settings. What I'm looking for is info on the RedHat 5.8 O.S. vs Netbackup. Are there any tweaks I need to make with this config that wasn't needed in RH 5.6 or Soalris 10?
None that I am aware off. The only teaks we do is some TCP/IP settings. The rest is left to default
Add the following values to /etc/sysctl.conf
On RHEL you may have other services that may impact the general performance, to name two: SELinux and iptables. If these security services are active, and you have very heavy network load, as in the case of a media server, you may see noticably lower performance.
Nicolai's network settings will definately improve the TCP performance. Another part to look into is the settings of the net driver/NIC HW. You can try with/without TCP checksum offloading etc.