do I really have to reboot Linux Server after I "override" FA Port Flag Bits?

that should do it, as long as HBAs log-off and logs back in, don't even need to mess with cables, just disable/enable port on the switch.

According to the EMC Host Connectivity Guide for Linux available from http://powerlink.emc.com at Support > Technical Documentation and Advisories > Host Connectivity/HBAs > EMC Host Connectivity Guide for Linux.

See page 71 of SC3 configuration on Linux

CAUTION

The SC3 and SPC-2 flags must only be manipulated as an offline event.

refer emc219981. HP-UX & Microsoft Windows Server 2008&2003, VMware ESX are supported for online SC3 flags enable

I can't see Primus cases anymore for some reason. 

But I believe that SC3 and SPC-2 must be set offline from manual above. 

However, can't I just pull the fibre cable (or disable at switch) and then change FA Port Flag Bit Overrides, and then re-enable SAN Switch port?  I have 2 x fabrics, so I'd have to do this one Fabric at a time.  But I wouldn't have to shut running applicaiton down. 

(If the flag bits are set incorrectly, you wonder how the application runs anyway?)

   Stuart

While servers can run without the proper flags set you wind up in the "unpredictable results can occur" bucket.  I had a customer whose AIX system would renumber its devices every time it was rebooted; turned out they were missing required flags.  Every time the system was rebooted they had to import every volume group; not good.

I guess it all comes down to the question of what the Operating System is going to be happy with. In my opinion, the fact that the flags get set based on the requirements for specific OSes tells me that the OS cares what the flags are and the flags have an effect on how storage is viewed. Changing this kind of thing on the fly is not something that most OSes are going to be happy with. And if they think they are happy with it, you may not be when things randomly start going south.

I would not even try to make this kind of change online... but that is just me. I don't think my Server Support guys would want to try that either. If they did I couldn't stop them, but I would reserve the right (in writing) to say "I told you so" the next time they so much as look at Storage as the root cause of anything going wrong on that host :-)

i would rather set the Flag setting at HBA level rather than Flags setting at FA port level.

My understanding from the beginning of the thread is that's what Stuart is trying to do. He's talking about using the commands to override the settings on the FA port for specific initiators.

In the end though I don't think it makes a difference for the one host exactly WHERE you make the change. The only real difference is that if you change it on the overrides for the initiator you only affect that one host instead of all hosts using that FA port.

I would still reboot the host either way.

Hi

Hope you are doing well !

I know we can set flags on initiators while the servers are online but it requires a reboot of server

I had a situation where i need to set flags on initiators for few windows servers but server team is not ready to reboot the servers on the same day or week.

If i do so, will it causes any errors in servers.

You may see errors on servers in the absence of these flags (e.g., you have the latest hba drivers and storport fix installed and not having SPC2 flags set) but having the flags enabled and not rebooting the server will not cause issues.

regards,

Saurabh