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Occasional Contributor
Posts: 16
Registered: ‎02-09-2004

Discovery of new LUNs

I can only see the new LUN after I disconnect and reconnect the fabric cable either on the server or on the switch. I am using 5100 switch and AMS 2100.

Or I have to reboot the server in order to see the new LUN.

Refresh does not help.

Valued Contributor
Posts: 931
Registered: ‎12-30-2009

Re: Discovery of new LUNs

Usually a rescan would do the trick.

This happens if you reboot a machine, but most (if not all) Osses can rescan without rebooting.

You're saying you have to fisically ave to remove en reattach the fibers which should not be needed.

Valued Contributor
Posts: 536
Registered: ‎03-20-2011

Re: Discovery of new LUNs

harish, i don't see any question marks in your message Smiley Surprised)

i'm sure that AMS is doing it's best to allow your host seeing any dynamic changes with the size and number of mapped LUNs -> in case if you configured the correct host mode and if you have a supported combination of OS level, HBA/firmware/drivers, and AMS microcode.

but... some HBAs really have to perform a fabric logout/login in order to see any disk changes. having said that, i mean that the disk array and the switch are not responsible for this. in this case, yes, sometimes you have to force this process, but usually it is enough to perform portdisable/portenable either on the HBA side or on the disk array side, instead of reconnecting the fabric cables or rebooting the devices.

regards, alexey

Super Contributor
Posts: 635
Registered: ‎04-12-2010

Re: Discovery of new LUNs

in case of a shared storage port (multiple servers are connected to a single storgae port) it is a bad solution to disable the storage port.

As well it is also not best practise to disable the server port in case of no redundant paths. This should be mentioned as well.

I aggree under some condition you need a reboot.

Andreas

Occasional Contributor
Posts: 16
Registered: ‎02-09-2004

Re: Discovery of new LUNs

Could be a HBA issue, I am using Brocade HBA 825. How do you initiate rescan for brocade hbas if it is not through HCM - Discover - Refresh.

Occasional Contributor
Posts: 5
Registered: ‎02-02-2011

Re: Discovery of new LUNs

Have you tried the re-scan as suggested before from the disk management console or cfgmgr

Occasional Contributor
Posts: 16
Registered: ‎02-09-2004

Re: Discovery of new LUNs

Windows..

yes tried almost everything even with emulex hbas...

Occasional Contributor
Posts: 16
Registered: ‎02-09-2004

Re: Discovery of new LUNs

Works perfectly with the other fabric that has 3900 switches and 9570 HDS storage.

Issue is with the new fabric that has 5100 switches and AMS2100 storage.

FOS is v6.4.1b

Host will not see the LUN assigned to it unless you either reboot the server, disable and enable the port either on the switch or HBA or disconnect the cable and reconnect the cable.

Once it can see the LUN, adding other new LUNs is not an issue.

Occasional Contributor
Posts: 5
Registered: ‎02-02-2011

Re: Discovery of new LUNs

May be you can verify the firmware and driver and s/w versions at host -> multipathing software -> hba -> storage.

Could be a bug somewhere...just a guess.

Occasional Contributor
Posts: 16
Registered: ‎02-09-2004

Re: Discovery of new LUNs

I my case seems to be a storage issue, Hitachi confirmed we need to upgrade the micro code to the latest version.

I hope this will fix my problem.

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