When 
a sybase database’s log is completely full, you won’t be able to add any log space to it. Attempting to add to the log produces a 3475 error:
00:0006:00000:00001:2014/01/08 09:03:09.09 server ERROR: Can't get a new log page in db 4. num_left=17 num_in_plc=17. 00:0006:00000:00001:2014/01/08 09:03:09.09 server Error: 1105, Severity: 17, State: 7 00:0006:00000:00001:2014/01/08 09:03:09.09 server Can't allocate space for object 'syslogs' in database 'mydb' because 'logsegment' segment is full/has no free extents. If you ran out of space in syslo gs, dump the transaction log. Otherwise, use ALTER DATABASE to increase the size of the segment. 00:0006:00000:00001:2014/01/08 09:03:09.09 server Error: 3475, Severity: 21, State: 7 00:0006:00000:00001:2014/01/08 09:03:09.09 server There is no space available in SYSLOGS to log a record for which space has been reserved in database 'mydb' (id 4). This process will retry at interval s of one minute.
So what to do? If you separate your data and log segments, you will need to temporarily add the log segment to a data device so the database can recover. Once it recovers, we can add space to the log and remove the log segment from the data device. For good measure, we run dbccs to correct any allocation issues that may be contributing to the out of log space.
Add the log segment to a data device (use sp_helpdb dbname to determine which data device has space):
exec sp_configure "allow updates", 1
go
update sysusages set segmap = 7 where dbid = 4 and lstart = 1492992
go
checkpoint
go
shutdown with nowait
goAdd space to the log:
alter database mydb log on mydevicel001 = 500
go
Before we do anything else, let’s run dbccs. Of course, you will want to run the dbccs without the fix option to identify if there are other issues prior to running with the fix:
exec kill_user_connections mydb
exec kill_user_connections mydb
exec kill_user_connections mydb
exec kill_user_connections mydb
exec kill_user_connections mydb
exec sp_dboption mydb, 'dbo use', true
exec sp_dboption mydb, 'single user', true
dbcc traceon(3604)
dbcc checkdb(mydb, fix_spacebits)
dbcc checkalloc(mydb, fix)
exec sp_dboption mydb, 'dbo use', false
exec sp_dboption mydb, 'single user', false
goIf no lingering issues, we can remove the log segment from the data device:
exec sp_dboption mydb, 'single user', true
go
use mydb
go
exec sp_dropsegment logsegment, mydb, mydeviced005
go
use master
go
exec sp_dboption mydb, 'single user', false
goSAP is fixing Bug CR 756957 in ASE 15.7 SP110 that may be the root cause of the 3475 error:
In certain circumstances, databases, including system databases, can incorrectly get into LOG SUSPEND mode, issuing message: “Space available in the log segment has fallen critically low in database ‘ < dbname > ‘. All future modifications to this database will be suspended until the log is successfully dumped and space becomes available.” This may happen even though there is much unreserved space in the database. The problem may also manifest in 3475 errors: “There is no space available in SYSLOGS to log a record for which space has been reserved in database < dbname > .”
