not able to telnet or access my server

[A Pandey]

Hello folks,

need some help:

i rebooted the web server this morning (friday) and the whole day it was working fine. about 7 pm my web master tells me that she cannot access the server using telnet OR otherwise.

i did not change any settings.

i don't have remote access to the console from my house during the weekend.

i did a ping and the server is responding.

but telnet responds with:connection closed by foreign host.

i use putty: connection reset by peer

any ideas would be good/welcome/almost necessary to say the least. we are a college so i need to get this up by monday latest.

thanks for your time and suggestions

[Michael Denney · Accepted solution]

Usually this is something like you ran out of procs for the system or procs per users or swap filled up. Could also be something like var filling up, but this is less likely. You will have get on the local console to see what messages are there.

[Yogeeraj_1]

hi,

as mentioned above, you will have to troubleshoot from the console itself!

you can also try to connect through another server in your infrastructure.. just in case...

also check if other services are responding...

kind regards
yogeeraj

[A Pandey]

what sor of trouble

shooting will be needed from console?

thanks ap.

[Clifford Chi]

Hi Pandey,

Here is what I can offer to check:

Understand that the "ping" doesn't get any respond from the system as well as telnet failed to the system.

Console login is required to troubleshoot. After login, you can check the following:

1. if you can login at console at all (and since we can't telnet to the system). The system might be hung. Perform "tc" via CM>. This will generate crash dump for analysis.

2. if login successful at console, verify the system is operational: application and command execute.

3. ping to other server IP and verify you are getting a response or not. If not, check lancard,

# lanscan
# ioscan -fnC lan <--- make sure they are CLAIMED
# ifconfig lanX <--- replace lanX with lan interface name you found from lanscan and make sure the output has "up" in the display. If it's not "up", use the following command to bring it "up"

# ifconfig lanX up

4. If above ok, check your lan cable. Swap it with another system lan cable if you have one and test telnet again.

[Yogeeraj_1]

hi ap,

you can also view your syslog file for any error occurrences.

more /var/adm/syslog.log

also check if your inetd process is still running

ps -ef|grep inetd


hope this helps too!

kind regards
yogeeraj

[A Pandey]

thank you for your responses. i will get to the console then let you folks know.

thanks again.

[A Pandey]

i got the syslog.log file...and i need help in using it to get and understand wht it means.

[Clifford Chi]

Hi,

Jan 7 09:46:31 wschp vmunix: file: table is full

You need to increment your kernel parameter, nfile, value. Above message indicate that your system is scarce of nfile resource.

[Yogeeraj_1]

hi,

You will have to review your kernel parameters.

You may proceed as follows:
1. sar -v 2 5
(file-sz is the problem)
2. kmtune -lq nfile
(check to see current value)
3. increase nfile via sam.

Note that you can also query the Sytem Table using Glance+

e.g.
SYSTEM TABLES REPORT

System Table Available Used Utilization High(%)
--------------------------------------------------------------------------------
Proc Table (nproc) 4096 685 17 17
File Table (nfile) 63498 6437 10 10
Shared Mem Table (shmmni) 512 14 3 3
Message Table (msgmni) 4096 2 0 0
Semaphore Table (semmni) 4096 26 1 1
File Locks (nflocks) 4096 468 11 11
Pseudo Terminals (npty) 60 0 0 0
Buffer Headers (nbuf) na 89250 na na

Also, note that the nfile parameter is generally calculated (in SAM) using the following formula:

nfile (19*(NPROC+16+MAXUSERS)/10+32+2*(NPTY+NSTRPTY+NSTRTEL))


hope this helps too!

kind regards
yogeeraj

[Tvs]

Hi pandey.

Login to the server thr console , and just restart the inetd process

inetd -c

and then try to stop and start the web service.

regards

Tvs