[Samba] SAMBA on HP-UX specific problem: Write Delay Failures! Why?!

[Chipev, Ivailo]

There seem to be problems with any SAMBA running on an HP-UX UNIX.

There are 2 available binaries (depots) for HP-UX:

samba-2.2.3a from http://hpux.connect.org.uk/ - The HP-UX Porting  Centre

and the latest

samba-2.2.5 from  http://de.samba.org/samba/ftp/Binary_Packages/hp/samba2.2.5/


The problems are:


We use SAMBA on a Databse server (HP-UX 11.11) and 4 Terminal Servers  under WIN2000 Server  have to constantly write files to SAMBA shares.  All seems to work fast and fine until "Delayed write errors" began to  appear on the Terminal Servers, resulting in many files not being saved  to disk. 

We had this problem with both binaries, although there was a noticeable  improvement when we upgraded to 2.2.5. But still now and then we got  empty files which is unacceptable for a live database.

Looking at the log files we spotted a curious error message which we  first thought was related to the problem but later we were proven  wrong:

[2002/08/08 12:00:35, 0] lib/util_sec.c:(52)
  Failed to set uid privileges to (0,30022) now set to (30022,30022)
[2002/08/08 12:00:35, 0] lib/util.c:(2456)
  PANIC: failed to set uid

[2002/08/08 12:00:35, 0] lib/util_sec.c:(52)
  Failed to set uid privileges to (0,30022) now set to (30022,30022)
[2002/08/08 12:00:35, 0] lib/util.c:(2456)
  PANIC: failed to set uid


On our server was installed the 2.2.3a version - from source which  enabled us to apply the following patch (by manually editing the file  below):

 /opt/samba_src/samba/source/lib/util_sec.c :


  *********************************************************************** *****/
 void restore_re_uid(void)
 {
+#ifdef USE_SETRESUID
+	setresuid(saved_ruid, saved_euid, -1);
+#else
 	set_effective_uid(0);
 	set_effective_uid(saved_euid);
 	if (getuid() != saved_ruid) setuid(saved_ruid);
 	set_effective_uid(saved_euid);
+#endif
 
 	assert_uid(saved_ruid, saved_euid);
 }

**********************************************************************


This fix came from a message by dsiebert at engineering.uiowa.edu way back  from Dec  8 20:47:29 1999 in the samba-patches discussion forum.

But this fix is impossible when installing from the depots.

The above fix stopped the error messages but did not stop the write  delay failures.

So why do I keep getting these write failures! The network is not  heavily loaded, the HP-UX server is very fast (4 RISC CPUs, 4 SCSI  arrays, lots of memory)

Have other HP-UX SAMBA users had a similar write delay problem?
I am planning to install from source the latest SAMBA. I read that for  HP-UX it is important that compile is run with gcc not cc. Has anybody  had a successful from source installation on HP-UX?


Please give me your hints, however remote....


Thanx!

Ivailo Chipev

Sofia Water PLC
Bulgaria