Re: The logical disk not on preferred path...Fast700 & AIX

From: sasa queer (sasa1973pk_at_yahoo.com)
Date: 04/30/04

  • Next message: David Martin: "Re: The logical disk not on preferred path...Fast700 & AIX" 
    Date: 29 Apr 2004 21:49:41 -0700

    Dears,
    I have been in same situation for last whole week.
    The luns are always moving away from their preferred path and as a result
    OS is loosing sight of Luns on FAst.
    IS it a bug in FAST Software or AIX handling of FAST.
    Any ideas

    !!!
    SASA

    sasa1973pk@yahoo.com (sasa queer) wrote in message news:<702930ee.0404262217.bdc1a9e@posting.google.com>...
    > Sorry Tom .
    > I really appreciate ur help and with ur answer realizing that i have
    > infact given really less information to go along.
    >
    > 1)
    > Yes i am using two SAN switches. However they are not intermixed to
    > form a single Fabric.
    > The cabling is done in this way that cables from each FC card ends
    > into seprate san switches.Zoning is done on each SAN Switch in this
    > way that each card should see seprate controllers on FAST Subsystem.
    > There are two FC on each AIX host.
    > One zone is also made to access tape drive. So one FC card's port on
    > switch is duplicated in two zone ( i.e CTLR-B Zone and Tapedrive
    > Zone).
    >
    > 2)The errors appearing on AIX host are saying " Array Controller
    > Switch " and "Array Configuration changed". I will post exact labels
    > in my next post but you are right that every time there is an error in
    > AIX error log which indicates that there are some event occur at FAST
    > subsystem level.
    >
    > And i am very much thankfull to you if you help me in pointing to
    > error which is present in SAN Configuration.
    > In addition to this i want to ask some basic questions:
    > 1) Can the Lun be accessed through two FC adapters per AIX host .I
    > think that it should be supported as there is RDAC driver present on
    > AIX.
    > 2) can a LUN be shared between two AIX hosts without using HACMP. I
    > mean using manual varyonvg and varyoffvg commands?
    >
    > Thanks in advance !
    > SASA
    >
    >
    >
    >
    > Tom Hoffmann <trh411@earthlink.net> wrote in message news:<pan.2004.04.25.03.12.53.514695@earthlink.net>...
    > > On Mon, 19 Apr 2004 09:09:40 -0700, sasa queer wrote:
    > >
    > > > Dears,
    > > > I have been captured in a strange situation. I have a number of P630
    > > > servers connect to a fast700 subsystem . one of the p630 have Stoirage
    > > > manager 8.3 installed and managing subsystem through direct management
    > > > technique ( no Sm agent working). Now the problem is that very
    > > > frequently " logical disk not on preferred path" error appearing on
    > > > subsysyem level and on AIX level the varyonvg commands hang and
    > > > filesystems hang up occur.
    > > >
    > > > A lot of fcs-array errors also appear in aix system log. AIX 5.2 Ml01
    > > > and fast manager 8.3.
    > > > can any body help me ?
    > >
    > > Well, you certainly have not given much to go on. SAN configurations can
    > > get very complex. Troubleshooting a SAN without any facts about how it is
    > > configured is impossible. Here are some questions:
    > >
    > > 1) Are you using a switched fabric to connect the hosts to the 700? If so,
    > > how many switches are in your configuration? How have you configured the
    > > zones on your fabric switches relative to the controllers on the 700? 2)
    > > How many FC adapters are in each host? Did you zone each adapter to a
    > > separate 700 controller?
    > > 4) What are the errors you are getting in the error log? I can make an
    > > assumption that they are FCP_ARRAY_ERROR messages, but why don't you
    > > provide the messages?
    > >
    > > BTW, in my experience, FCP Array errors are almost always the result of a
    > > mis-configured SAN.

  • Next message: David Martin: "Re: The logical disk not on preferred path...Fast700 & AIX"

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