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while we suspect a 3rd party program might be causing the issue or at least helping it along , what we are trying to do is isolate or prove it.

any suggestion or ideas are welcome as we are running out

system info

udt - 8.1.2

redhat - 7.9

when unidata locks up

 showud shows all the processes running yet any ECL sessions are locked up trying to login via udt hangs, we turned on error logging but the log file only shows the start of unidata and nothing else

udtmon - does show a little disk activity

we did straces on the udt processes including trying to open a udt session 

attached is an strace of a udt session and an ipcs output when the system is hung

any ideas or suggestions are welcome as well have been stumped, we are talking to the 3rd vendor as well and like I said we are not positive that the issue but we have seen their process using a lot of memory and cpu

stopping unidata and starting it back up and everything works fine, for a while, there is no pattern to when it locks up, its been various days and various time, including the week-end when the system is barely doing anything.

thanks

dougc



------------------------------
Doug Chanco
Universe Programmer
Self Registered
graham NC US
------------------------------

while we suspect a 3rd party program might be causing the issue or at least helping it along , what we are trying to do is isolate or prove it.

any suggestion or ideas are welcome as we are running out

system info

udt - 8.1.2

redhat - 7.9

when unidata locks up

 showud shows all the processes running yet any ECL sessions are locked up trying to login via udt hangs, we turned on error logging but the log file only shows the start of unidata and nothing else

udtmon - does show a little disk activity

we did straces on the udt processes including trying to open a udt session 

attached is an strace of a udt session and an ipcs output when the system is hung

any ideas or suggestions are welcome as well have been stumped, we are talking to the 3rd vendor as well and like I said we are not positive that the issue but we have seen their process using a lot of memory and cpu

stopping unidata and starting it back up and everything works fine, for a while, there is no pattern to when it locks up, its been various days and various time, including the week-end when the system is barely doing anything.

thanks

dougc



------------------------------
Doug Chanco
Universe Programmer
Self Registered
graham NC US
------------------------------
Try and go to the demo account and see if it lets you in. Also check that there aren’t locks running against VOC or guide or some such.
Try and go to the demo account and see if it lets you in. Also check that there aren’t locks running against VOC or guide or some such.

we tried other account and could not get in as for checking for locks we cannot access the system is there a way in unidata/redhat to list the locks outside of unidata?

we have a ticket opened with rocket i see that 8.1.2 is end of life in sept .....



------------------------------
Doug Chanco
Universe Programmer
Self Registered
graham NC US
------------------------------

we tried other account and could not get in as for checking for locks we cannot access the system is there a way in unidata/redhat to list the locks outside of unidata?

we have a ticket opened with rocket i see that 8.1.2 is end of life in sept .....



------------------------------
Doug Chanco
Universe Programmer
Self Registered
graham NC US
------------------------------

Doug,

One possibility is that the system is running out of UNIX kernel resources. Check 'ulimit' per user and system default and also the kernel parameters as per the installation and admin. guides - e.g.:

semmnu 3 * (number of concurrent sessions*) + (number of authorized users / 4)
shmmni Must be greater than SHM_GNTBLS
msgmni Non-RFS: 10 + the number of concurrent journal processes if you are using UniData Journaling.
RFS: ((number of authorized users / 4) * 2) + 10
semmni NUSERS/NSEM_PSET + 1 
semmns NUSERS*2) + 10  

Please note that 'authorised users' really means the number of concurrent sessions and if using Device Licensing then the appropriate multiplier should be applied. Similarly UniData assumes a maximum ratio of 1 PHANTOM per 4 interactive sessions (as in the calculations above). If using a larger percentage then upsscale the calsulations to match.

A full 'udtdiag' (run as root) would be the next step - also - do you use EDA, RFS or U2 Replication? 

Regards

JJ



------------------------------
John Jenkins
Thame, Oxfordshire
------------------------------

we tried other account and could not get in as for checking for locks we cannot access the system is there a way in unidata/redhat to list the locks outside of unidata?

we have a ticket opened with rocket i see that 8.1.2 is end of life in sept .....



------------------------------
Doug Chanco
Universe Programmer
Self Registered
graham NC US
------------------------------

Also worth checking this in 8.2

UDT-16314 Prior to this release, if udtelnetd was unable to set a write lock on the utmp file, which is a special non-text data file in the /var/run/utmp directory on Linux systems that records all logins and logouts from the system, the udtelnetd process might have hung while holding a read lock on utmp. This behavior would cause all subsequent login attempts to hang until the udtelnetd process was removed. This issue has been resolved. For more information about the utmp file, refer to the utmp man page in Linux.

Regards

JJ



------------------------------
John Jenkins
Thame, Oxfordshire
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