Manually running a dbbackup command on a computer with SQL Anywhere V10.0.1
causes the web server to stop working with the database server. We just
figured out what was causing the problem.

Test machine OS: Windows XP

This is a stand alone development machine with web server and SQL Anywhere
installed on same box.

dbbackup -c"connectionstringhere" -y -x d:\dbbackup\

After running this command, I must stop and start IIS to have the web site
accessible.

Should I be able to backup the database live with IIS running and not cause
any bad side effects?

Yes. Sure you should.

Is there any errors reported by the server?
Is the server blocking other connections while this is apparently hung?
Does the backup actually complete?
Does this occur every time you run dbbackup?
Does the backup statement behave the same way for you?

There is a chance that you may have exceed some
limit someplace. This could also be a temporary
condition if you could just leave the web server
running long enough.

One thought I have is you may not have enough threads
to satisfy all concurrent requirements (see -gn). Another
thought I have is you have some virus scanner, or defragger
or other system process preventing the log from being
renamed, deleted and recreated; try it removing the -x
switch.

From the latest 10.0.1 ebf readme I see these entries that
may be relevant to you:

================(Build #3560 - Engineering Case
#480055)================
In some circumstances, backups could have taken longer to complete than
expected.
This problem would have been noticed only if the total size of the database
files was greater than 2GB, and was more likely to be noticed when backing
up a very small fraction of that database size (e.g., such as when doing
a TRANSACTION LOG ONLY backup with a small transaction log). This has been
fixed.

================(Build #3505 - Engineering Case
#471413)================
If a BACKUP statement was executed that used one of the TRANSACTION LOG
backup
options, and the database did not use a transaction log file, then the
server
would have crashed. This has been fixed. The server now returns the error
"Syntax error near 'backup option'".

================(Build #3536 - Engineering Case
#475293)================
A client-side backup (ie using the Backup utility or calling the dbtools
function DBBackup) that truncated the log, could have created a backed-up
log file that was invalid. When this occurred the logfile would have
appeared
to be too short; i.e., the end offset of the backed-up log did not match
the starting offset of the current log. This problem did not occur when
the log was not truncated, or when calling the BACKUP DATABASE statement.
This has been fixed.


There is also 1 or 2 issues worth looking into if you are using database
mirroring.


"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote

The backup finishes fine. The web server can no longer talk to the database
server. After a lot of testing, it appears there is a problem with SQL
Anywhere and IIS. The .NET web page states that a timeout occurs. This may
be a bug with SQL Anywhere. I would have to uninstall the software and
start applying patches and EBF's until I can fix the problem and apply newer
EBF's to duplicate the problem. This way I can track down which ebf started
causing the problem.

"Nick Elson" <@@@nick@@@.@@@elson@sybase@@@.@@@com@@@> wrote

Interesting indeed. I am suspicious this may not
be a new behaviour in our software but an OS, FS,
and system utilities thing.

When the server hangs like this, is ther a *new* transaction
log present? If not, I would lean towards virus checking,
defragging or some other system utility blocking the file
from being deleted/created-anew. Normally I would
expect to see a fatal error or assertion error logged.

Are you logging with -o? Or just the event log? Do
you not see a Fatal Error or Assertion Error in either?

Since the backup ***seems*** to have completed,
did you get chance to test to see if it is a valid backup?


"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote

I think my first assumption that it was directly related to the backup was
wrong. IIS can hang even when no backup has been run. I have to restart
IIS at least three times a day as a work around. I am going to back rev SQL
Anywhere this weekend to see if the problem goes away.

"Nick Elson" <@@@nick@@@.@@@elson@sybase@@@.@@@com@@@> wrote

Phew. Thanks for letting us know.

Good luck with that.

"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote

I backed reved to V10.0.1.3488. It's been only 24 hours but it's still
running. I will let it run for 1 week and If I have no problems I will
reinstall the latest EBF and see if the problem starts again.

"Nick Elson" <@@@nick@@@.@@@elson@sybase@@@.@@@com@@@> wrote

The problem happened less often but it still had problems. I changed the
connection string in the .NET code to use shared memory instead of TCP/IP.
I also upgraded back to V10.0.1.3559.

"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote

The server seems to be working for 4 days without a problem. I will give it
5 days more to make sure.

"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote

Still running into problems with IIS and timeouts. I applied EBF 3579
Saturday. I noticed an ADO.NET update...

================(Build #3560 - Engineering Case #480211)================
When one connection was blocking on a WAITFOR statement, all other
connections
were also blocked until it finishes. This problem has been fixed.

I hope this is what is happening to me.

"Bob Piskac" <bob (AT) pbsoftware (DOT) com> wrote