File system corruption when 1 copy of a mirror powered off

From: Jeffrey Ross (jeffrey.rossATairways.co.nz_at_no.spam)
Date: 06/06/03 

Date: Fri, 6 Jun 2003 17:41:48 +1200

Hi.

I am using AIX 4.3.3.0 with 2 x RS/6000 44P each connected to 2 x SSA
enclosures each with 4 x 4.5GB disks. Each disk contains 1 logical volume
(except the first which also contains a 1 PP jfslog). The first SSA
enclosure's logical volumes have been mirrored to those on the second
enclosure. I use varyonvg and mount to make the disks available on
whichever machine is to utilise them.

When I drop the power on encloseure 1 I expect the disks on enclosure 2 to
keep the 4 file systems visible to the machine that they are mounted on.
This happened once out of 5 tests. On at least one occasion 5 of the disks
became stale. Sometimes a write to one of the filesystems will fail after a
minute. To recover often a varyoffvg, exportvg, importvg, varyonvg, fsck,
mount will work, but twice varyonvg has failed with the need to run
redefinevg and chpv to recover the file systems. Files that are written
while one enclosure is power off are seldom actually written to disk.

Is there something obvious that I have overlooked?

The SSA loops are quite simple. Each goes from machine 1 to an SSA tower to
machine 2, and thence directly back to machine 1. Details are:
SSA 1 port 1 to machine 1 port A1
SSA 1 port 4 to machine 2 port A1
machine 2 port A2 to machine 1 port A2 (completing the first loop)
SSA 2 port 1 to machine 1 port B1
SSA 2 port 4 to machine 2 port B1
machine 2 port B2 to machine 1 port B2 (completing the second loop)

Thanks,
Jeffrey.

Relevant Pages

  • Re: "Delayed write failed" while firewire drive is not doing anything??
    ... Ian Wrote: ... > I have a 4-bay external firewire enclosure, ... > "Delayed write failed" error on one or more of the disks (usually the ... while there were no delayed write errors withe these drivers, ...
    (microsoft.public.windowsxp.hardware)
  • Re: [9fans] Petabytes on a budget: JBODs + Linux + JFS
    ... I have this SATA backplan-inside-enclosure with 3x Barracuda 7200 series 1 TB disks attached. ... The enclosure lights for the two 7200.11's respond the right way but the one that's ought to represent the 7200.12 freaks out. ... The tech at the enclosure vendor tells me some Seagate disks don't support control of enclosure lights. ... drives appear hard to swap out. ...
    (comp.os.plan9)
  • Re: "Delayed write failed" while firewire drive is not doing anything??
    ... >Ian Wrote: ... >> I have a 4-bay external firewire enclosure, ... let alone when I'm not actually using the disks. ... >while there were no delayed write errors withe these drivers, ...
    (microsoft.public.windowsxp.hardware)
  • Re: [9fans] Petabytes on a budget: JBODs + Linux + JFS
    ... equivalent technology on SATA disks for controlling enclosure facilities? ... for control.) ... TB disks attached. ... The enclosure lights for the two 7200.11's respond the ...
    (comp.os.plan9)
  • Re: Button of the computer not work properly
    ... reformatting customer boot disks, just for the hell of it. ... an enclosure and a bare disk drive, ... is to find one with a fan. ... The power dissipation of the 2.5" and 3.5" drives is quite different. ...
    (microsoft.public.windowsxp.hardware)