How to roll-back "Not supported" items

[jarek]

My SNMP agent has some number of items which are sometimes not available (they are dynamic). I.e. when some process is down I don't see his variables.
When it happends, zabbix is changing state of time to "Not supported", and I need manually change it back to "Monitored".
Is there any way to avoid such case ?

[Nate Bell]

When I run into values that are sometimes unsupported, I have been making scripts that check the value before giving it to Zabbix, and change the value to a bogus one that Zabbix will accept. However, these have all been executed with the Zabbix_Agent and UserParameters in the agent's config file. I'm not sure about doing this with the SNMP_Agent.
Perhaps there is a cleaner way to do this. I'd certainly be interested in hearing about it.
Nate

[jarek]

I've added new configuration parameter NoStatusChange to zabbix_server.conf.
Setting this parameter to 1 blocks this behaviour of zabbix. From yesterday it works for me.
This is patch to server.c (1.1alpha10)
=================================
79d78
< int CONFIG_NO_STATUS_CHANGE = 0; // Added by JT 2005.06.22
249d247
< {"NoStatusChange",&CONFIG_NO_STATUS_CHANGE,0,TYPE_ INT,PARM_OPT,0,1},
474,475c472
< if( CONFIG_NO_STATUS_CHANGE == 0 ) // Added by JT 2005.06.22
< DBupdate_item_status_to_notsupported(item.itemid, error);
---
> DBupdate_item_status_to_notsupported(item.itemid, error);
=================================

[Alexei]

I plan to introduce an additional status for monitored parameter - not available. 'Not available' items will be periodically rechecked.

For example, if you try to get filesize[/var/log/messages] and the file does not exists, status will be set to "Not available" (recoverable). However, if agent doesn't support filesize[], the status will be set to "Not supported" (unrecorevable).

[jarek]

Great idea, but the question is what means "Not supported" in case of SNMP ? If I have some dynamic values, which appears when some process is up, but they don't exist at all when process is down, they are unsoported or unavailable ?
I think, that better solution is to add some additional parameter to each item, which tell that the value shouldn't be blocked.
I'm using zabbix to monitor systems operated by non-technical people. I wan't to give them a tool, which will have absolutely fixed configuration. I don't even want to give them administration password.

[Alexei]

Could you tell more about the dynamic SNMP items? Are they related to network interfaces?

[jarek]

Generally almost every value in SNMP can be dynamic. The best example is the list of processes running on machine. Every process has some number of attributes like CPU usage, allocated memory, priority etc.
Of course this set of values exist only if the process is running, when process terminates values are no more available. Even more, when process is restarted they will appear with different OIDs because the process number will be different.
In my case, I have some set of values which have fixed OIDS, but they exists only when the process is running.
Generally, most of attributes supplied by SNMP depends on state of the system. Network interfaces, mounted filesystems, tcp connections may not exist at boot time, but can appear afterwards.
It means that you cannot distinguish when some attribute is not supported, or currently not available.
I think that the only case when some attribute may be treated as unsupported is the case when SNMP cannot resove its name or oid is invalid (message: Unknown Object Identifier).
Your idea with rechecking "not available" values looks very good, but in case of SNMP, Item status, should be changed to "unsupported" only manually.
I see there also some other way: change of staus may be triggered also by SNMP trap, but this is risky, as the traps are delivered without confirmation.
By the way, handling of SNMP traps by zabbix should be also changed. I have some idea how, and if you will agree I can do it.

best regards
Jarek.

[rdg]

This is a very importand issue for me. Right now I have to activate around 100 items everytime someone restarts a server, or even worse, whenever there are problems I will loose important data since the item turns into not supported. A new status "Not available" will solve this problem.

It seems that you have a solution to this problem Jarek. It would be really nice to see this implemented in the next release of Zabbix.

Thanks

Robert

[rdg]

Not supported, value #2 has unknow type [129]

I see this problem every now and then and it remains in the ZABBIX 1.1beta2. Sometimems items turns "Not supported", i've notice that this happens if I stop the SNMP agent for a short time or even if i have intermittent problems in the network(the Internet in my case).

Basically we have three options.
1. Make sure internet is stable at all times, In my case that involves one ISP in Europe and one in SouthAmerica plus a number of unknown carriers in between. In addition I have to make sure the server i monitor is up and running at all time. Not even a restart can be allowed.

2. Change the Items back to "Monitored" everytime Zabbix turns them "Not supported".

3. Item status, should be changed to "Not supported" for type SNMP only manually by Zabbix as previously suggested in this thread.



I would vote for option number three above

Thanks

Robert

[edeus]

I like the idea of having an extra option so that I can enable forced checking (not a delayed check) for specific items...

Otherwise there could be a lot of junk for items that arent actually supported but are in my zabbix_agentd.conf.

[mucknet]

I like the idea of having an extra option so that I can enable forced checking (not a delayed check) for specific items...

Otherwise there could be a lot of junk for items that arent actually supported but are in my zabbix_agentd.conf.

I too would prefer a forced checking option. I have problems with SQL server performance counters. Sometimes the counters completely disappear, and zabbix marks them unsupport, and I have to manually re enable them. I've been bit by it more than once

If I could choose a Manual override for that, it would be excellent. Or if ALL unsupport and not available items attempted reconnect periodically (at a configurable period!), it would be excellent.

I'm eagerly awaiting a resolution to this

[rushowr]

I too, vote for absolutely must have this fixed somehow ASAP. Zabbix has been extremely solid for us (other than a strange occasional crash of the suckerd and/or agentd), and I use it to monitor a nationwide VOIP ITSP.

However, the bosses really really love the screens, and get extremely mad when a graph that shows the current number of active calls on a server suddenly gets no data and the item shows as "Not Supported".

I've tried to explain that it's because of occasional unreadable data passed by the SIP server, but they don't care, and are actually moving to remove the monitoring because of that ONE thing.

Manually fixing it is not a problem, except the other admin patently refuses to remember how to do it, and calls me ANY time it goes down....

Please Please Please, let's get that one fixed.

(also, the stability of the daemons, as I get a crashed sucker or agent at least once a week)

[cameronsto]

Maybe in the meantime, you could write a quick cron job to just update all disabled checks to enabled via the database every 5 minutes or so. Something like:

update zabbix.items set status = 0 where status = 3;

Note: The sql should be correct, but I haven't tested it. Be sure to test it before using on your production systems.

-cameron

[Alexei]

Automatic rechecking of unsupported parameters is in CVS. Will be released as part of 1.1beta3.

[rdg]

Great!

Many thanks

/R