Zabbix URL Ping - check if IP address changes

[LukeAB93UK]

Hello,

I am curious as I have had a request come in from a Sys admin.

They want to know if a certain url fails over to the backup host by having Zabbix ping the IP Address and report the result and if it changes to a different IP address it will then alert with a trigger I write that it has failed over.

Is it possible to do so with Zabbix without running a custom script?

Thanks

[cyber]

If you ping an IP address, then it either answers or not... it will not change.. If you ping a hosts name, then lookup is done and that IP is pinged... But Zabbix will not catch changes there, as it will record either ping succeeded or not... 0 or 1...

[LukeAB93UK]

If you ping an IP address, then it either answers or not... it will not change.. If you ping a hosts name, then lookup is done and that IP is pinged... But Zabbix will not catch changes there, as it will record either ping succeeded or not... 0 or 1...

Hmm. I need to know if the URL pings from a different IP address and has failed over to the secondary host. Is there anyway to do that as both IPs are always pingable.

[markosa]

So, you have host name aa.bb.com? It may respond from IP 1.2.3.4 (main) or 4.5.6.7 (spare) and you want to know when it changed from main to spare? External check with fping might do it, something like this: fping -A -d aa.bb.com and then you would make trigger when IP changed from fping output. Or, do you want to know if web-service has changed host?

[LukeAB93UK]

So, you have host name aa.bb.com? It may respond from IP 1.2.3.4 (main) or 4.5.6.7 (spare) and you want to know when it changed from main to spare? External check with fping might do it, something like this: fping -A -d aa.bb.com and then you would make trigger when IP changed from fping output. Or, do you want to know if web-service has changed host?

You are exactly right. I want to know when www.abc.com for example changes from pinging from 1.2.3.4 to 4.5.6.7 so we know its failed over.

[markosa]

As you said, both do respond to ping all the time,right? Then you must check service status/availability, for example in case of www-service you could put just static web page to both servers with different contents, server A has it's IP in that page and server B has it's IP and when querying www.abc.com/mystaticpage you would get always page from server which is working and from there you can see and make trigger for change.

[LukeAB93UK]

As you said, both do respond to ping all the time,right? Then you must check service status/availability, for example in case of www-service you could put just static web page to both servers with different contents, server A has it's IP in that page and server B has it's IP and when querying www.abc.com/mystaticpage you would get always page from server which is working and from there you can see and make trigger for change.

I shall propose that idea to the team and see waht they say thank you for the suggestion.

[ISiroshtan]

Seems a bit extreme for me to setup a seperate page for such monitoring. If your ping of URL changes IP on failover I would assume you have some kind of failover based on DNS name resolution update? If so, you could try to monitrong result of DNS resolution. On Zabbix you could do a small script in extranl scripts folder with code something along the lines

nslookup URL_HERE | grep -A2 URL_HERE | grep Address | grep -oE '([0-9]+\.?)*'

Test the script if it properly fetches the IP and detects failover. If it works then setup Zabbix External item check and run the script -> setup the trigger for change between last and before last values.

[cyber]

There is an item

net.dns.record[<ip>,name,<type>,<timeout>,<count>,<protocol>]

Maybe its worth to investigate....