[SOLVED] nagios/nrpe problem

Message

kolcon · Post by **kolcon** » Mon Dec 07, 2009 7:43 am

I have a strange problem with nrpe...

######
on the remote monitored host :
net-analyzer/nagios-nrpe-2.12-r102 USE="command-args ssl"

/etc/nagios/nrpe.cfg:
command[check_home]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /home

running :
/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /home
DISK WARNING - free space: /home 329711 MB (17% inode=-);| /home=1509720MB;1471544;1655487;0;1839431
######

on the "central" host:
# /usr/lib/nagios/plugins/check_nrpe -H ip_of_remote
NRPE v2.12

# /usr/lib/nagios/plugins/check_nrpe -H ip_of-remote -c check_home
NRPE: Unable to read output

Any ideas why? should I open a bug?
Thank you for any ideas...

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 11:37 am

Hi,

My check_disk binary is here:

/usr/nagios/libexec/check_disk

Check the path is correct on your remote host.

Rich.

kolcon · Post by **kolcon** » Mon Dec 07, 2009 11:59 am

richard.scott wrote:Hi,

My check_disk binary is here:

/usr/nagios/libexec/check_disk

Check the path is correct on your remote host.

Rich.

libexec -> /usr/lib/nagios/plugins
it is the same thing....

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 12:41 pm

Is there anything in the logs on the remote host?
I had something from nrpe in there when I had this problem.

kolcon · Post by **kolcon** » Mon Dec 07, 2009 12:43 pm

richard.scott wrote:Is there anything in the logs on the remote host?
I had something from nrpe in there when I had this problem.

Not much :
Dec 7 12:58:42 ricbhost nrpe[2867]: Connection from XXX.XXX.XXX.XXX port 47073
Dec 7 12:58:42 ricbhost nrpe[2867]: Host address is in allowed_hosts
Dec 7 12:58:42 ricbhost nrpe[2867]: Handling the connection...
Dec 7 12:58:42 ricbhost nrpe[2867]: Host is asking for command 'check_disk' to be run...
Dec 7 12:58:42 ricbhost nrpe[2867]: Running command: /usr/nagios/libexec/check_disk -w 10 -c 5 -p /
Dec 7 12:58:42 ricbhost nrpe[2867]: Command completed with return code 3 and output:
Dec 7 12:58:42 ricbhost nrpe[2867]: Return Code: 3, Output: NRPE: Unable to read output
Dec 7 12:58:42 ricbhost nrpe[2867]: Connection from XXX.XXX.XXX.XXX closed.

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 12:49 pm

kolcon wrote:libexec -> /usr/lib/nagios/plugins
it is the same thing....

Not if its a recent install on Gentoo.

on a recent install of nagios-plugins they all go in /usr/lib/nagios/plugins

I'd double check to make sure.

Rich.

kolcon · Post by **kolcon** » Mon Dec 07, 2009 12:55 pm

richard.scott wrote:
kolcon wrote:libexec -> /usr/lib/nagios/plugins
it is the same thing....
Not if its a recent install on Gentoo.

on a recent install of nagios-plugins they all go in /usr/lib/nagios/plugins

I'd double check to make sure.

Rich.

Yes, they are there in /usr/lib/nagios/plugins, the other directory is just a symlink

# emerge -pv nagios-plugins

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild R ] net-analyzer/nagios-plugins-1.4.14 USE="ldap mysql nagios-ping nagios-ssh samba snmp ssl suid -ipv6 -nagios-dns -nagios-game -nagios-ntp -postgres -radius -ups" 0 kB

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:02 pm

kolcon wrote:Yes, they are there in /usr/lib/nagios/plugins, the other directory is just a symlink

How did you get the symlink then?

i've just emerge these:

Code: Select all

 # equery list nagios
[ Searching for package 'nagios' in all categories among: ]
 * installed packages
[I--] [  ] net-analyzer/nagios-nrpe-2.12-r102 (0)
[I--] [  ] net-analyzer/nagios-plugins-1.4.13-r1 (0)

and I don't have a /usr/nagios/libexec symlink

Code: Select all

# cd /usr/nagios/libexec
-su: cd: /usr/nagios/libexec: No such file or directory

What does this show on your remote system:

Code: Select all

 # equery files nagios-plugins | grep disk
/usr/lib/nagios/plugins/check_disk

Rich

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:05 pm

good question about the symlink

# equery files nagios-plugins | grep disk
/usr/lib/nagios/plugins/check_disk
/usr/lib/nagios/plugins/check_disk_smb
/usr/lib/nagios/plugins/contrib/check_snmp_disk_monitor.pl

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:09 pm

Perhaps NRPE doesn't like symlinks?

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:19 pm

richard.scott wrote:Perhaps NRPE doesn't like symlinks?

Can be, however when I change it to:
command[check_disk]=/usr/lib/nagios/plugins/check_disk -w $ARG1$ -c $ARG2$ -p $ARG3$

it still behaves the same...

When I run the command directly under root, it prints out DISK OK etc.... I wonder if it
could be permissions problem?

nrpe is running under user nagios, all the plugins are owned by nagios:nagios

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:34 pm

what does this show on the remote host:

Code: Select all

# cat /etc/nagios/nrpe.cfg | grep "^command"

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:36 pm

richard.scott wrote:what does this show on the remote host:
Code: Select all
# cat /etc/nagios/nrpe.cfg | grep "^command"

# cat /etc/nagios/nrpe.cfg | grep "^command"
command_timeout=60
command[check_users]=/usr/lib/nagios/plugins/check_users -w 5 -c 10
command[check_load]=/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 30,25,20
command[check_hda1]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /dev/hda1
command[check_home]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /home
command[check_zombie_procs]=/usr/lib/nagios/plugins/check_procs -w 5 -c 10 -s Z
command[check_total_procs]=/usr/lib/nagios/plugins/check_procs -w 150 -c 200
command[check_disk]=/usr/lib/nagios/plugins/check_disk -w $ARG1$ -c $ARG2$ -p $ARG3$

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:40 pm

do you have allowed_hosts= set?

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:41 pm

richard.scott wrote:do you have allowed_hosts= set?

Yes and you can see it in the log I pasted

Dec 7 12:58:42 ricbhost nrpe[2867]: Connection from XXX.XXX.XXX.XXX port 47073
Dec 7 12:58:42 ricbhost nrpe[2867]: Host address is in allowed_hosts

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:45 pm

why does that log extract from earlier show this:

/usr/nagios/libexec/check_disk

and your nrpe.cfg has this:

/usr/lib/nagios/plugins/check_disk

Rich

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:48 pm

richard.scott wrote:why does that log extract from earlier show this:

/usr/nagios/libexec/check_disk

and your nrpe.cfg has this:

/usr/lib/nagios/plugins/check_disk

Rich

I changed that in the nrpe.cfg based on your hint to possible symlink problem...
now it says
Dec 7 14:15:24 ricbhost nrpe[3107]: Host is asking for command 'check_disk' to be run...
Dec 7 14:15:24 ricbhost nrpe[3107]: Running command: /usr/lib/nagios/plugins/check_disk -w 10 -c 5 -p /
Dec 7 14:15:24 ricbhost nrpe[3107]: Command completed with return code 3 and output:
Dec 7 14:15:24 ricbhost nrpe[3107]: Return Code: 3, Output: NRPE: Unable to read output

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 1:53 pm

try this in nrpe.cfg

Code: Select all

-p "$ARG3$"

I think the "" marks helped me?

kolcon · Post by **kolcon** » Mon Dec 07, 2009 1:56 pm

richard.scott wrote:try this in nrpe.cfg
Code: Select all
-p "$ARG3$"
I think the "" marks helped me?

Thanks, good hint, however did not help
Dec 7 14:56:00 ricbhost nrpe[3209]: Host is asking for command 'check_disk' to be run...
Dec 7 14:56:00 ricbhost nrpe[3209]: Running command: /usr/lib/nagios/plugins/check_disk -w 10 -c 5 -p "/"
Dec 7 14:56:00 ricbhost nrpe[3209]: Command completed with return code 3 and output:
Dec 7 14:56:00 ricbhost nrpe[3209]: Return Code: 3, Output: NRPE: Unable to read output

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 2:03 pm

ok, what about this:

Code: Select all

ssh remote_ip /usr/lib/nagios/plugins/check_disk -w 10 -c 5 -p "/"

kolcon · Post by **kolcon** » Mon Dec 07, 2009 2:08 pm

richard.scott wrote:ok, what about this:
Code: Select all
ssh remote_ip /usr/lib/nagios/plugins/check_disk -w 10 -c 5 -p "/"

# ssh remote_ip /usr/lib/nagios/plugins/check_disk -w 10 -c 5 -p "/"
DISK OK - free space: / 33309 MB (55% inode=-);| /=26696MB;59996;60001;0;60006

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 2:26 pm

try and add " 2>&1" to the end of your command definition in nrpe.cfg.
This will echo back stderr, which may tell you what's wrong.

kolcon · Post by **kolcon** » Mon Dec 07, 2009 2:35 pm

richard.scott wrote:try and add " 2>&1" to the end of your command definition in nrpe.cfg.
This will echo back stderr, which may tell you what's wrong.

Now THAT was a good hint.... as I though, permissions problem on the folder
/var/lib/nagios

It is fixed now...

Thank you again for your support

richard.scott · Post by **richard.scott** » Mon Dec 07, 2009 2:42 pm

kolcon wrote:Thank you again for your support

No prob, glad its working