VxVM Root disk encapsulation and ufs logging - is it valid?

Hi,
Is it valid to use the UFS mount option "logging" for an encapsulated root disk under VxVM ?
I searched through sunsolve and saw some info about older VxVM releases.
I use 5.0
Thanks
Edited by: AssafL on Nov 11, 2007 1:12 PM

There are some versions of VxVM where that combination is not recommended. I don't recall if all interactions are corrected in 5.0. You might want to search on the Symantec support site.
Darren

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    So, admin and group had read-write-exec access to the Mac HD, but others had nothing, which I thought odd. It seems like you should at least be able to boot the computer to the login screen, and if a user is not admin or admin group, you cannot login, but I guess that's not the way it's set up.
    So, I tried:
    chmod o+r Macintosh HD
    Then, I reran verify disk permissions. Again, I got the same "Underlying..." error. So I tried
    chmod o+x Macintish HD
    I then reran verify disk permissions, and it ran fine and the suggested that the Macintosh HD volume permissions should be set to:
    rwxrwxr-t
    So, I had the Disk Utility repair it to the way it should be, and now it all seems fine.
    This suggestion basically did not come from any Apple Support people or any forums, and it seemed like such an easy fix that I'm surprised nobody (at least nobody I've found) has had the same problem or needed the same fix.
    Further, I think figured out what happened. I took my computer to my local tech support guys because I wanted to turn off sharing for this MBP. So, under Macintosh HD, somebody changed the permissions under "Everyone" from "Read Only" to "No Access".
    It turns out that doing this basically creates the whole problem above by making the Macintosh HD unmountable or inaccessible.
    I find it truly odd that it would be so easy to remove access to the computer for mounting purposes, but this is the only thing I can think of. The tech guy realized his error and apologized and was also surprised it was so easy to hose the computer.
    Anyway, this is partially a warning to everyone as well as a possible fix for the blue screen problem, especially since it was a solution I could not find anywhere.
    Maybe Apple Support will see this and for its next update at least make a warning box when people try to remove "Read Only" access for "Everyone".
    Good luck.

    If your Mac still boots and runs most applications correctly, but applying Software Update packages fails and you decide to run Disk Utility to Verify Permissions and it fails almost immediately with the "underlying task reported failure on exit" explore this posting. If you see other errors, have slow/varied disk performance, or hear nasty grinding/clicking sounds you have a much more serious problem this solution isn't for you.
    Use Applications, Utility, Console and check the messages appearing there each time you try Disk Utility. If you see:
    Failed to open database on '/'. Error 14, 13, Permission denied.
    You may have had your permissions reset on the receipts db. Which is found in
    /Library/Receipts/db/a.receiptdb
    At this point you have to enter the dark world of the Terminal and use a unix shell (command line).
    If you are not comfortable doing find a Unix/Linux power user.
    The simple fix for me was to open Applications, Utilities, Terminal and do
    sudo chmod 755 /Library/Receipts/db/a.receiptdb
    This allowed Disk Utility to read the file and move on to repairing permissions.
    When things generate error messages in the GUI part of Mac OS X ...always go check the messages in the logs via the Console in Utilities. These messages are 'down a level' and get you much closer to the real problem.
    Note that I did follow the instructions in Apple kb TS1901
    http://support.apple.com/kb/TS1901
    which did not help at all. Same problem each time:
    xxxx-imac:Volumes user$ diskutil verifyPermissions /
    Started verify/repair permissions on disk disk0s2 Macintosh HD
    $<3>Error -9972: The underlying task reported failure on exit
    $<3>[ + 0%..10%..20%..30%..40%..50%..60%..70%..80%..90%..100% ]
    Finished verify/repair permissions on disk disk0s2 Macintosh HD
    Error detected while verifying/repairing permissions on disk0s2 Macintosh HD: The underlying task reported failure on exit (-9972)
    Now I wonder what changed the permissions on the receipts database file? I am off to use find and date fields to see what changed the permissions file last (my is dated sometime in November!).
    flatiswhereitsat

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