Curl+SNMP, Compare and Trigger

[harvey]

Hi All,

I'm using SNMP to monitor some routers. One of the metrics is the the firmware of the router. The router manufacturer offers a URL that can be curl'd with to show the latest firmware.

What I would like to do it to be able to run a script locally on the Zabbix server that looks up the latest version and then some way compare the output of the snmp and curl value and if they are different trigger an alert.

Is this possible, if so how??

Many thanks.

[kloczek]

I'm 100% sure that the same information about firmware version already served in OIDs tree
KISS principle ..

[harvey]

Hi All,

I'm using SNMP to monitor some routers. One of the metrics is the the firmware of the router. The router manufacturer offers a URL that can be curl'd with to show the latest firmware.

What I would like to do it to be able to run a script locally on the Zabbix server that looks up the latest version and then some way compare the output of the snmp and curl value and if they are different trigger an alert.

Is this possible, if so how??

Many thanks.

To clarify:-

"What I would like to do it to be able to run a script locally on the Zabbix server to get the latest version and then compare the output to the snmp value and if they are different trigger an alert."

[harvey]

I'm 100% sure that the same information about firmware version already served in OIDs tree
KISS principle ..

The actual installed router firmware version is accessible via SNMP but newer (not installed versions) are not accessible via SNMP. I want to trigger an alert when the routers firmware is out of date.

[harvey]

I've made some progress, I created a script in '/usr/lib/zabbix/externalscripts' and created an item using the 'External Check' type. I now have two items, one pulling the installed firmware via SNMP and the latest version via CURL. Both item types are set as text and can see the values.

I have now created a trigger with the following expression:-

{MikrotikSNMPv3AES-SHA:1.3.6.1.4.1.14988.1.1.4.4.0.last()} <> {MikrotikSNMPv3AES-SHA:mikrotik_latest.sh.last()}

However, I am getting the following error:-

Cannot evaluate expression: expected numeric token at "6.43.11) <> (6.43.12)".

I suspect <> is trying to compare numerical values, is there anyway to compare two strings together?

[harvey]

I've made some progress, I created a script in '/usr/lib/zabbix/externalscripts' and created an item using the 'External Check' type. I now have two items, one pulling the installed firmware via SNMP and the latest version via CURL. Both item types are set as text and can see the values.

I have now created a trigger with the following expression:-

{MikrotikSNMPv3AES-SHA:1.3.6.1.4.1.14988.1.1.4.4.0.last()} <> {MikrotikSNMPv3AES-SHA:mikrotik_latest.sh.last()}

However, I am getting the following error:-

Cannot evaluate expression: expected numeric token at "6.43.11) <> (6.43.12)".

I suspect <> is trying to compare numerical values, is there anyway to compare two strings together?

Or somehow create a numerical representation of the two strings and compare those? Or md5 hash the strings and compare?

[Evgeniy]

One solution is to delete "." and compare numeric values.

[harvey]

One solution is to delete "." and compare numeric values.

Thanks, actually thats what I have been working on using preprocessing regex but I'm not very good with regex. if you have any idea what to put in for pattern and output that would be appreciated.

[Evgeniy]

Not sure what will work, try, e.g. (\d*)\.(\d*)\.(\d*) -------------- \1\2\3

[harvey]

Thanks! That worked. I still want the pretty version available for viewing so I duplicated the items and applied the regex in pre processing on the duplicates. I was then able to create the trigger against the duplicated items.

Is there any way to apply the regex within the trigger expression so I don't need the duplicate items?

Hope that makes sense!