Seesion canceled with ANR0488W, as backup is running OK.

Hi list,

I have a node (tsm 5.2.3 on Windows 2003 server) having unusualy (for us
at least ..) big files to backup : > 100 GB. 
Unfortunately, everytime I try to do a backup from those files, TSM
server (5.2.2.1 on AIX 5.2) breaks the session after a while with
ANR0488W, complaining that througputdatathreshold and/or
throughputtimethreshold have been reached, despite the fact that backup
is running properly with an average 10MB/s rate. The session is then
reestablished by client, and the whole cycle begins again. 

Q sess on server looks like this :

             Sess Number: 3.235.353
             Comm. Method: Tcp/Ip
               Sess State: RecvW
                Wait Time: 0 S 
               Bytes Sent: 631
              Bytes Recvd: 25,0 G
                Sess Type: Node
                 Platform: WinNT
              Client Name: PAC2KT15
      Media Access Status: Current output volume(s):  000536,(2583
Seconds)
                User Name: 
Date/Time First Data Sent: 27.08.2004 10:44:54
   Proxy By Storage Agent: 

Client error log looks like this :

08/27/2004 10:44:39 sessSendVerb: Error sending Verb, rc: -50
08/27/2004 10:44:39 ANS1809W Session is lost; initializing session
reopen procedure.
08/27/2004 10:44:54 ANS1810E TSM session has been reestablished.

TSM activity log looks like this (filtered only for this node):

08/27/04 09:55:00     ANR0406I Session 3234823 started for node  (WinNT)
(Tcp/Ip
                       pac2kt15.corp.panorg.com(2681)). (SESSION:
3234823)      
08/27/04 10:44:39     ANR0488W Session 3234810 for node PAC2KT15 (WinNT)
termin 
                       ated - transfer rate is less than (30) and more
than (60 
                       ) minutes have elapsed since first data transfer.
(SESS 
                       ION: 3234810)

08/27/04 10:44:54     ANR0406I Session 3235353 started for node PAC2KT15
(WinNT)
                       (Tcp/Ip pac2kt15.corp.panorg.com(2753)).
(SESSION: 32353 
                       53)

08/27/04 10:54:28     ANR0406I Session 3235418 started for node PAC2KT15
(WinNT)
                       (Tcp/Ip pac2kt15.corp.panorg.com(2760)).
(SESSION: 32354 
                       18)

08/27/04 10:54:28     ANR0403I Session 3235418 ended for node PAC2KT15
(WinNT). 
                        (SESSION: 3235418)


Due to log pinning problems, I can't afford to extend our
troughputdata/time thresholds (having respectively 30 and 60), and
anyway I don't get it why server would consider the session as inactive,
as it is running flawlessly.
Could anyone provide an explanation/solution for this behaviour ?

Arnaud 

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