Posts Tagged ‘san’

Boot from SAN is not necessarily one of the easiest things in the world; however, Cisco UCS does take away a lot of the complexity with its Service Profiles and associated Boot Policies. I’m not going to get into an exhaustive post around booting from SAN on Cisco UCS as I think most people have readily documented and how it works. However one important caveat to keep in mind is that the Cisco M81K-R does not have an “HBA BIOS” that is typically available in the Emulex or Qlogic HBA/CNA’s that we’re all familiar with. If you’re unfamiliar with the HBA BIOS utilities, this is typically as Cntrl+E or Cntrl+Q sequence that you can type in as a host is booting up so you can have the HBA log into the fabric and scan for its available luns.

Not to turn into a Debbie Downer, but there is a very easy way to circumvent this caveat and make use of the lovely UCSM CLI. As the host is booting, you can connect the VIC adapter and have it log into the fabric and list its luns. Couple this with the dialogue from the UCS Boot Policy and we can easily troubleshoot any SAN booting issues. This method negates any need for having a traditional HBA BIOS created for the Cisco VIC family and demonstrates from the real power of the UCSM CLI.

It should also be noted that once the host has completed booting, the host drivers will take over and the VIC drivers will not be accessible for scanning the fabric. See below for some of the command walk through.

For the example of this post, we’ll be logging into a Xiotech array which has a WWPN ID of 20:00:00:1F:93:00:12:9E. Our Service Profile is attached to Blade 1/1 in our UCS deployment (which is a B200-M2 and thus the adapter is located at slot 1).
So first we’ll connect down to our VIC firmware:
UCS-6200-TOP-A# connect adapter 1/1/1
adapter 1/1/1 # connect
adapter 1/1/1 (top):1# attach-fls
Now we’ll list our vnic ID’s and force the VIC to log into the SAN fabric
adapter 1/1/1 (fls):5# vnic
—- —- —- ——- ——-
vnic ecpu type state   lif
—- —-   —- ——- ——-
7    1       fc   active  4
8    2       fc   active  5
adapter 1/1/1 (fls):4# login 7
lifid: 4
ID     PORTNAME                                          NODENAME                          FID
0:    20:00:00:1f:93:00:12:9e  00:00:00:00:00:00:00:00  0xa70400
Looks like we’ve successfully logged into the fabric as we’ve got a successful PLOGI ( see above ) and now we can report out which luns we have access to
adapter 1/1/1 (fls):5# lunmap 7
lunmapid: 0  port_cnt: 1
lif_id: 4
PORTNAME                                               NODENAME                          LUN                           PLOGI
20:00:00:1f:93:00:12:9e  00:00:00:00:00:00:00:00  0000000000000000  Y

adapter 1/1/1 (fls):6# lunlist 7
vnic : 7 lifid: 4
– FLOGI State : flogi est (fc_id 0xa70804)
– PLOGI Sessions
– WWNN 20:00:00:1f:93:00:12:9e WWPN 20:00:00:1f:93:00:12:9e fc_id 0xa70400
– LUN’s configured (SCSI Type, Version, Vendor, Serial No.)
LUN ID : 0x0000000000000000 (0x0, 0x4, XIOTECH , 3BCC01C4)
– REPORT LUNs Query Response
LUN ID : 0x0000000000000000
– Nameserver Query Response
– WWPN : 20:00:00:1f:93:00:12:9e

Great – everything is working as expected and our Windows 2008 server successfully booted from our Xiotech array. Special thanks to Jeff Allen and some other helpful Cisco people in pointing this awesome feature. 

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