Re: Atape Driver's Alternate Pathing and TSM

        Hmm, your configuration is similar to mine except that I have a
3494 library and you have a 3584, so take what I say with a grain of
salt.

        So you have 4 actual 3592 tape drives? How many FC adapters in
the host? It looks like you only have 1 FC card configured/zoned on the
TSM server, as all the tape drives are going to the adapter in slot
"0A-08-02". Not much redundancy there.

        Compare that to one of my TSM servers where I have 2 FC adapters
and 4 drives:

 $ lsdev -Cctape
lmcp0        Available              LAN/TTY Library Management Control
Point
rmt0.29fb.0  Available 17-08-01-PRI IBM 3592 Tape Drive (FCP)
rmt0.29fb.1  Available 31-08-01-ALT IBM 3592 Tape Drive (FCP)
rmt1.2b2d.0  Available 17-08-01-PRI IBM 3592 Tape Drive (FCP)
rmt1.2b2d.1  Available 31-08-01-ALT IBM 3592 Tape Drive (FCP)
rmt2.8118.0  Available 17-08-01-PRI IBM 3592 Tape Drive (FCP)
rmt2.8118.1  Available 31-08-01-ALT IBM 3592 Tape Drive (FCP)
rmt3.8119.0  Available 17-08-01-PRI IBM 3592 Tape Drive (FCP)
rmt3.8119.1  Available 31-08-01-ALT IBM 3592 Tape Drive (FCP)

        Notice that the primary paths to the drives go to the adapter in
slot 17-08-01 and the alternate paths go through the FC adapter in slot
31-08-01. 

Which cable are you pulling to test this?

If I pull the fibre line to one of my FC cards, it fails over just fine.
If ~you~ were to pull the FC line going to the FC card on your TSM
server, that's the only path available and everything is going to stop
working. I can see why your configuration isn't working.


Ben

 

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Dameon White
Sent: Tuesday, October 11, 2005 12:15 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Atape Driver's Alternate Pathing and TSM

I am trying to take advantage of the Atape driver's Alternate Pathing
feature.  When I do a lsdev -Cc tape I see:

rmt0 Available 0A-08-02-PRI IBM 3592 Tape Drive (FCP)
rmt1 Available 0A-08-02-PRI IBM 3592 Tape Drive (FCP)
rmt2 Available 0A-08-02-PRI IBM 3592 Tape Drive (FCP)
rmt3 Available 0A-08-02-PRI IBM 3592 Tape Drive (FCP)
rmt4 Available 0A-08-02-ALT IBM 3592 Tape Drive (FCP)
rmt5 Available 0A-08-02-ALT IBM 3592 Tape Drive (FCP)
rmt6 Available 0A-08-02-ALT IBM 3592 Tape Drive (FCP)
rmt7 Available 0A-08-02-ALT IBM 3592 Tape Drive (FCP)
smc0 Available 0A-08-02     IBM 3584 Library Medium Changer (FCP)

But when I do a backup to the primary drives and then disconnect the
cable to test a failure, the alternate drive(s) do not take over.

Within TSM I have 4 drives (rmt0-3 defined).

Am I missing a step?

Thanks for your help.

DW