Drizzt95
asked on
Run TOP from crontab
I don't know too much about unix, but am wanting to find a way to regularly have the ouput of top sent to a file. I run a line which works perfectly, but when I add it to a cron job it always fails. The line I am running is:
top -d1 > /rhc/nt1/top.txt
It works when I run it, but it won't work from a cron job. There is a couple of processes that we need to keep an eye on and if they get in the top 10 then i need to be notified. If i can't do it with top, is there any other way to get the top 10 processes.
top -d1 > /rhc/nt1/top.txt
It works when I run it, but it won't work from a cron job. There is a couple of processes that we need to keep an eye on and if they get in the top 10 then i need to be notified. If i can't do it with top, is there any other way to get the top 10 processes.
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ahoffmann
-d 1 does not work in cron (check your mails send by crond:)
ahoffmann, if u ran it via a shellscript, will it not work then?
no, 'cause top requres a tty for most options, and with cron there is no tty
it does not make a difference if there is a (useless) shell around top
it does not make a difference if there is a (useless) shell around top
ok, thanks for that
I tried running via shellscript, it does seem to work (well it work cos of tty - now that I know), but I have not tried it with cron
I tried running via shellscript, it does seem to work (well it work cos of tty - now that I know), but I have not tried it with cron
Reason why I suggested a shell script is so that more can be done, instead of running just top.
For example, you may want to email the results or whatever.
Its also useful for validation ie. directory specified still exists or is not writable, easier to log errors
For example, you may want to email the results or whatever.
Its also useful for validation ie. directory specified still exists or is not writable, easier to log errors
ASKER
I did originally have it running from a script, but that didn't work either. It ran fine when i execute it myself, but when it runs via a cron job, it just creates an empty file everytime.
Drizzt95, does ahoffman's idea work?
question for ahoffman
if term was set to xterm, in the shell script and top run then, would that make a difference?
TERM=xterm
export TERM
question for ahoffman
if term was set to xterm, in the shell script and top run then, would that make a difference?
TERM=xterm
export TERM
> if term was set to xterm, in the shell script and top run then, would that make a difference?
no
the reason is the tty, which is a device, not the term(inal)
no
the reason is the tty, which is a device, not the term(inal)
ok., thanks ahoffman
ASKER
ahoffman's idea didn't work either, just created a blank file.
If i try running the crontab entry from unix, I get the following error:
/usr/bin/top: syntax error at line 1 : `(' unexpected
The command I was running is:
cron_env /usr/bin/top -d1 > /rhc/nt1/top.txt
The cron entry I have is:
0,5,10,15,20,25,30,35,40,4
Like i said, I don't know too much about unix, but every other entry in crontab uses the cron_env. I've tried replacing it with "su sys -c "/usr/bin/top -d1 > /rhc/nt1/top.txt", which also creates a blank file, but doesn't cause any errors.
If i try running the crontab entry from unix, I get the following error:
/usr/bin/top: syntax error at line 1 : `(' unexpected
The command I was running is:
cron_env /usr/bin/top -d1 > /rhc/nt1/top.txt
The cron entry I have is:
0,5,10,15,20,25,30,35,40,4
Like i said, I don't know too much about unix, but every other entry in crontab uses the cron_env. I've tried replacing it with "su sys -c "/usr/bin/top -d1 > /rhc/nt1/top.txt", which also creates a blank file, but doesn't cause any errors.
ASKER
I managed to get it working. The statement below seems to work from a cron job, for some reason the " > /rhc/nt1/top.txt" part was causing the problem.
top -d1 -f /rhc/nt1/top.txt
top -d1 -f /rhc/nt1/top.txt
> If i try running the crontab entry from unix, I get the following error:
> /usr/bin/top: syntax error at line 1 : `(' unexpected
this could never be from the command I suggested (except *your* /usr/bin/top is a shell script already)
> /usr/bin/top: syntax error at line 1 : `(' unexpected
this could never be from the command I suggested (except *your* /usr/bin/top is a shell script already)
ASKER
It only gets that error when I run it with the cron_env in front of it, which all of our cron jobs have. If i run it without the cron_env then it also fails in a cron job (works fine when run manually):
cron_env /usr/bin/top n 1 > /rhc/nt1/toptest.txt
/usr/bin/top: syntax error at line 1 : `(' unexpected
cron_env /usr/bin/top n 1 > /rhc/nt1/toptest.txt
/usr/bin/top: syntax error at line 1 : `(' unexpected
what does cron_env do?
is /usr/bin/top a script?
is /usr/bin/top a script?
ASKER
absolutely no idea, it was set up before I started here. I've just continued to do as what was done in the past.
/usr/bin/top is an executable.
I'm not sure if this would make any difference, but I did just notice that there is an alias set up for top. It is: alias -x top='top -s1 -n10 -q'
I'm not sure if that would affect it at all.
To be honest, I'm not too worried, we'll only have this server for another couple of months and I've managed to get it working, which is all I wanted.
Seeing as though you both showed me a bit, I'll split the points evenly between you.
Thanks for your help.
/usr/bin/top is an executable.
I'm not sure if this would make any difference, but I did just notice that there is an alias set up for top. It is: alias -x top='top -s1 -n10 -q'
I'm not sure if that would affect it at all.
To be honest, I'm not too worried, we'll only have this server for another couple of months and I've managed to get it working, which is all I wanted.
Seeing as though you both showed me a bit, I'll split the points evenly between you.
Thanks for your help.
no worries. Glad you got going though
> but I did just notice that there is an alias set up for top
that's why I always used /usr/bin/top in all my posts ;-)
that's why I always used /usr/bin/top in all my posts ;-)