User/Group that executes the SMS media to /dev/ttyS0

[entorno]

Hello all,

I've got two Zabbix boxes running. One for testing / learning, the other being one that we will use in production.

The test box is a SLES10, and the production box is a CentOS 4.4

When I was testing with SMS media on the SLES, I had to chmod o+rw /dev/ttyS0 , which just was a temp fix.

However, now on the CentOS, I need to know which user zabbix sends the SMS's as, as it does not have permision to use /dev/ttyS0.

Anyone tell me which user it is please?

Many thanks

[Calimero]

Didn't you create a zabbix user and a zabbix group when installing zabbix ?

Anyway "ps aux | grep zabbix_server" will tell you what user zabbix is running as.

[entorno]

yeah, I added zabbix user and group

Just added him to the group used by the device... see if it works.

[entorno]

nope...

However it does work if I chmod o+rw /dev/ttyS0

So, it's not sending the SMS as user zabbix :-|

Any developer who could advise please?

Kind regards

[Alexei]

If ZABBIX server is running under user 'zabbix', group 'zabbix', then obviously the device must have read-write permissions for either user or group 'zabbix'.

[entorno]

Hi Alexei,

As I said, I tried that. I added the user "zabbix" to the group used by the device:

uucp:x:14:uucp,zabbix

The zabbix user can send strings to ttyS0 no problem, yet the webUI reported it was unable to open /dev/ttyS0 in the error column.

The only way so far to get it to work is to add "other" rw perms.... so I guess when Zabbix sends the SMS message, it is not as user zabbix.. would you agree?

[Calimero]

yeah, I added zabbix user and group

Just added him to the group used by the device... see if it works.

Log in (or "su") as zabbix and issue the command "id". It will list what groups zabbix is in.

It should output something like:
zabbix@hostname:~$ id
uid=1000(zabbix) gid=1000(zabbix) groups=1000(zabbix),1001(group_for_device)

Permissions on the device are of course g+w I guess ?

By the way did you restart zabbix server ? There's some kind of caching (per session ?) I think.

[entorno]

[zabbix@zabbix ~]$ id
uid=501(zabbix) gid=501(zabbix) groups=14(uucp),501(zabbix)

The box had a reboot after... so yeah, the zabbix_server has been restarted

[Calimero]

What aboud ownership/permissions of the device (ls -l) ?

[entorno]

Hi, as I've said,

it's now been set to:

crw-rw-rw- 1 root uucp 4, 64 Dec 19 13:56 /dev/ttyS0

And Zabbix sends SMS messages ok...

However, when it's set to:

crw-rw---- 1 root uucp 4, 64 Dec 19 13:56 /dev/ttyS0

It can't open the device :-\

[artesvida]

zabbix user permissions

Has anyone found a solution/explanation? I have the same problem:

1) zabbix_server running under the "zabbix" user account:
ps -ef | grep zabbix
zabbix 3341 1 0 May04 ? 00:00:08 /usr/local/bin/zabbix_server
zabbix 3422 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3423 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3424 3341 0 May04 ? 00:01:20 /usr/local/bin/zabbix_server
zabbix 3425 3341 0 May04 ? 00:00:25 /usr/local/bin/zabbix_server
zabbix 3426 3341 0 May04 ? 00:34:37 /usr/local/bin/zabbix_server
zabbix 3427 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3428 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3429 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3430 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
zabbix 3431 3341 0 May04 ? 00:00:00 /usr/local/bin/zabbix_server
me 20737 23731 0 11:07 pts/0 00:00:00 grep zabbix

2) zabbix user account in the "dialout" group:
me@server:~$ su zabbix
Password:
zabbix@server:/home/me$ id
uid=1001(zabbix) gid=1001(zabbix) groups=20(dialout),110(admin),1001(zabbix)

3) modem is on /dev/ttyS1:
ls -l /dev/ttyS1
crw-rw---- 1 root dialout 4, 65 2007-05-04 09:43 /dev/ttyS1

4) I can successfully open the modem when I su to the zabbix user.

5) zabbix_server daemon fails to open the modem, unless I open it up to everyone (chmod 666 /dev/ttyS1).

6) Yes, I have restarted the zabbix_server daemon, and I have also restarted the server.

I don't really want to open the modem up to everyone, and besides it should just work. Anyone figure out why this is happening?

[Alexei]

Do you start ZABBIX server uder root account? If so, the daemon automatically changes its ownership to zabbix:zabbix during startup sequence.

[artesvida]

Yes, it's started under the root account.

So, since I see that you keep referring to the daemon's ownership as zabbix:zabbix, does that mean that it doesn't matter that the zabbix user is also a member of the "dialout" group? Is the zabbix_server daemon going to have ONLY the permissions of the zabbix user and the zabbix group?

[Alexei]

Exactly! ZABBIX gets uid and gid from /etc/password and sets ownership of running zabbix_server accordingly. It ignores secondary groups.

You may either start ZABBIX under 'zabbix' or change primary group to 'uucp'.

[rugwiza]

Sms

Dear Entorno,
I ve followed the conversations you did with senior members, and eventually u succeeded to configure zabbix to send sms.
As I am new to the monitoring system, can u please a step-by-step scenario on how to do it?
Thanks