Did you ever receive the error 17283 “Procedure ‘sp_extendsegment’, Line 182 ‘tempdev1′ is reserved exclusively as a log device.” error? You can get the 17283 error when there is a device fragment that contains only the log segment. Part of the problem is when you extend the log segment onto a device, it will usually drop all other segments so it becomes ‘log only’.
device_fragments size usage created free kbytes ------------------------------ ------------- -------------------- ------------------- ---------------- master 8.0 MB data and log Dec 16 2004 4:09AM 3376 tempdev1 1024.0 MB data and log Dec 16 2004 7:02AM 1044480 tempdev1 256.0 MB data and log Mar 9 2005 10:49AM 261120 tempdev1 256.0 MB log only Mar 9 2005 10:54AM not applicable tempdev1 488.0 MB data and log Mar 9 2005 12:10PM 497760 tempdev1 256.0 MB data and log Mar 11 2005 2:03PM 261120 tempdev1 244.0 MB data and log Mar 11 2005 3:09PM 248880 tempdev1 200.0 MB data and log Jun 1 2005 12:33PM 204000 tempdev1 200.0 MB data and log Jul 8 2005 2:55PM 203808 tempdev1 200.0 MB data and log Jul 21 2005 2:54PM 204000 tempdev1 1000.0 MB data and log Feb 6 2006 1:11PM 1020000
So, how to fix this? Well, Sybase doesn’t provide any way to do so without modifying the system tables.
use master exec sp_configure "allow updates", 1 go begin tran go
since we are dealing with tempdb and we want data and log on all the device fragments, we can make a blanket update. We would make the update more selective if we had other requirements (update only one row or something)
update sysusages set segmap = 7 where dbid = db_id("tempdb")
if the number of rows updated exceed the number of rows for the database, issue a ‘rollback’
select segmap from sysusages where dbid = db_id("tempdb")
all good? if so, issue a ‘commit’
commit tran go exec sp_configure "allow updates", 0 go
Now that the system table is updated, we need to refresh the dbtable memory structure so that the changes we made become ‘live’
dbcc dbrepair(tempdb, remap) go
That’s it! It’s fixed and running with the segmaps without having to restart ASE. Wasn’t that easy?
