Trashed Disk Labels Under Sun OS 3.5

[Ian Dall]

In article <3555 at helios.ee.lbl.gov> envbvs at epb2.lbl.gov (Brian V. Smith) writes:
->writes:
->< 
->< How come when I mount all of the disk as swap or anything in an 'a'
->< partition on a local Micropolis 1355 disk connected to one of our
->< clients the disk label gets trashed?  I have to recover the label with
->< diag.  Allocating file systems and swap on the disk shouldn't trash the
->< disk label, should it?  Sorry if this question was asked before.
->
->
->Never put a swap area on partition 'a' of any drive.  The superblock
->will be written over by swapping. 
->This is true for Ultrix (2.x and 3.0 at least).  I'm not sure
->about other os's.
->Make at least a small 'a' partition followed by the 'b' swap partition.

Well, at SysV got something right. The version I have (at least) keeps
the partition table (= "label") on the first sectors of the disk and
this is stuck in its own partition. On my system partition "6" is the
first cylinder (0) of the disk and has no file system on it. You arrange
for other partitions to NOT include cyinder 0.

I see no reason why one could not do this with SunOS.  I think that it
is a really bad idea to have swap/mkfs etc. have special code to skip
the first cylinder if it is the "a" partition.


-- 
 Ian Dall           life (n). A sexually transmitted disease which afflicts
                              some people more severely than others.
idall at augean.oz