You probably ought to vary the paths and chpids offline (VARY OFF PATH xx FROM 
ALL followed by VARY OFF CHPID nn) for the ones in question. When service is 
restored, vary them back on in the reverse order, CHPID then PATH. 

It isn't as issue with VM, either. If the Linux guests are using minidisks (as 
opposed to dedicated or attached disks), the only thing that they might notice 
is an increase in I/O contention. 

If Linux is using dedicated disks, then you will need to address its needs to. 
I cannot give you any insight into that. 

Regards,
Richard Schuh

 -----Original Message-----
From:   VM/ESA and z/VM Discussions [mailto:[EMAIL PROTECTED]  On Behalf Of 
Ranga Nathan
Sent:   Friday, February 17, 2006 1:47 PM
To:     [email protected]
Subject:        Temporary disruption to channel paths - impact on z/Linux?

We have a problem in our disk array. One of the ficon channel controller 
cards is down. Our ops wants to swap it today. This will require downing 
3 channel paths out of 6 that are shared to z/VM.

In the past, I have always shutdown all Linux instances and z/VM and 
brought it back after the card swap.

If three out of the six are suddenly unavailable, would z/VM ignore them 
and use the only three that are available? When all the six are 
available when both cards are functioning, will z/VM auto-detect and use 
the channels?

Would this all be transparent to the Linux guests?

Apparently this is not an issue on the z/OS side.

-- 
__________________
Ranga Nathan
Work: 714-442-7591

Reply via email to