Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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Can you have a look in /var/log/maillog and post any error messages here please? Also, what happens when you're logged into the box and type `telnet localhost 25` at a command prompt? Does it let you connect? If it did, try typing `ehlo localhost` - do you get something like the following:
250-[snip] Hello localhost [127.0.0.1], pleased to meet you
250-AUTH DIGEST-MD5 CRAM-MD5 LOGIN PLAIN
If you can connect locally, the next step is to look for config changes that may be stopping remote connections.
Ok, I've continued to look all over and am basically getting more confused. It's definitely a load problem of some kind, but how to determine what is causing this remains a mystery. In addition, I'm at a loss to fix it. Any ideas, please? I think it's important to say that this server is also running apache, samba, and all the usual networking cucca...
You are correct - sendmail will reject connections when the server is under heavy load. Have you tried running `top`? It's real time, not historical so it needs to run when the server is actually rejecting mail.
The alternative is to check the mail log, get date/times when the rejections happened and try to match that date/time against logs for other likely candidates (cron jobs, ftp, web server, etc.). There's no guarantee that what was happening will appear in the logs, so top may be the best bet.
top? Unknown to me. Please elaborate. Thanks for the help!
NM, Googled it. Wow, this is cool. I just realized that mysqld is running 99.9% of my CPU! What could cause this? I've also noticed, through phpMyAdmin, that there are some weird entries into tables on my databases as of late. Have I been hacked? How do I check?
Killing MySQL now...[/edit]
Last edited by WorldBuilder; 01-09-2006 at 08:36 PM.
mysql has been killed. Good lord, my server is dual proc and it was cranking on them both...
I am moderately knowledgeable about php and MySQL, but no expert. System running fine now (with MySQL off), but I will ask some MySQL experts why it is doing this now? Anyone here, perhaps? Has been running fine until yesterday apparently. Now, as soon as I login, it starts cranking out 99.9% cpu. Weird...
Thank you very much for all your help. You steered me in the right direction.
BTW, ls -AlR /u | more gives me:
No such file or directory
Is there a specific directory you wanted me to run that from?
PS. I DO have a "u" directory in /usr/share/terminfo and when I ran ls -AIR on that I got the following:
It looks like the process output was truncated at the 'u' instead of showing the full path to the mysqld base directory (that's just what top does when it doesn't have a lot of space.
I wouldn't be worried about the stuff in /usr/share/terminfo/u, I have the same sort of stuff there.
For your last post though...
publicsmtp1.com doesn't resolve to anything when I look up the domain. Can you post the whole ps -ef output? I'd like to look up the PPID (parent process id) and user for that line and see which process (and who) owns it. Also, try running:
grep 'publicsmtp1' /var/log/maillog*
grep 'publicsmtp1' /var/log/*
It may be something simple like one of your webapps is sending some email - it will show up in /var/log/maillog if that's the case.