freebsd stable - Apr 2003 - sharing scsi disk beetween two freesbd's ...

I want to use one scsi disk with two redondant servers, mounted r/w on server A
and r/o on
server B.
Everything works, except that when I write data from server A, I can't read
it on server B
before un-mounting the disk ant re-mounting it... (with AND without
soft-updates)

Is there any way to mount a disk r/o keeping in sync with real disk data ?

Thank you.

-- 
Geoffroy DESVERNAY

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:
:I want to use one scsi disk with two redondant servers, mounted r/w on server A
and r/o on
:server B.
:Everything works, except that when I write data from server A, I can't read
it on server B
:before un-mounting the disk ant re-mounting it... (with AND without
soft-updates)
:
:Is there any way to mount a disk r/o keeping in sync with real disk data ?
:
:Thank you.
:
:-- 
:Geoffroy DESVERNAY

    The machines cache the disk data in memory, so if one machine has read
    a track and the second machine writes it, the first machine will not see
    the changes until it flushes its caches (which may be never).  

    Also, what you are doing is extremely dangerous.  Even the machine with
    the read-only mount is going to assume that the data on the disk is not
    going to change out from under it, and when it does you could crash the
    kernel.

    A better solution would be to attach the disk to a single machine and then
    export the filesystem to the second machine via NFS. 

						-Matt