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service monitoring in dual fail over servers

Posted: Fri Jul 14, 2017 4:39 am
by padu_3891
Hello Team ,

I have situation here that i want to monitor set of services for monitoring an application in HostA or HostB . Host A and B are kind of fail over environment , i mean the application will be running at any one of the host at a time . Application will be switched to other server automatically when the currentserver is down .

Is there any idea to have both the server IP for a single host and then we can have all the services mapped to this new comman host .

Service should check the host which have the application up .

Re: service monitoring in dual fail over servers

Posted: Fri Jul 14, 2017 2:26 pm
by bolson
Hello,

Can you please provide more information, ie: what OS? What application? What mechanism for "failing over" to HostB? and what version of Nagios Core?

Thank you!

Re: service monitoring in dual fail over servers

Posted: Fri Jul 14, 2017 2:28 pm
by tgriep
You could use the plugin called check_multi and it could be configured to generate an alert when both of the services are down on both hosts if that is what you are looking for.
https://exchange.nagios.org/directory/P ... ti/details
Take a look at it and see if this is what you are looking for.
Else, you can search that site for another plugin.

Re: service monitoring in dual fail over servers

Posted: Thu Jul 20, 2017 8:25 am
by padu_3891
Sorry for delay in repond .

The above link provided explains about the chek..but the download URL is not working . i think this check is been removed .

Re: service monitoring in dual fail over servers

Posted: Thu Jul 20, 2017 8:59 am
by mcapra
Here's the github page for check_multi in case the previous website isn't working for you:
https://github.com/flackem/check_multi

Re: service monitoring in dual fail over servers

Posted: Thu Jul 20, 2017 10:53 am
by Pitone_Maledetto
Hi,
you could use custom macros.
I have this setup so I can check the ILO and the host in the same host configuration.
host_address ip_of_server_A
_serverB_ip ip_of_server_B

You need to configure the service and commands to suite this configuration but works pretty good.

If you reckon that this is a good solution for you I could provide some configuration examples.

Regards

Sent from the mobile client - Forum Talker

Re: service monitoring in dual fail over servers

Posted: Thu Jul 20, 2017 4:57 pm
by tmcdonald
Thanks for the assist, @Pitone_Maledetto!

Re: service monitoring in dual fail over servers

Posted: Fri Jul 21, 2017 2:32 am
by Pitone_Maledetto
@tmcdonald you are welcome :)

just an example of how I would roughly make it work.

Command definition

Code: Select all

# 'check_load_ssh'
define command{
        command_name    check_serverB_load
        command_line    $USER1$/check_by_ssh -H $_HOSTBADDRESS$ -l your_log_name -C "/usr/lib/nagios/plugins/check_load -w $ARG1$ -c $ARG2$"
    }
Host definition

Code: Select all

define host{
        use                     generic-host
        host_name               serverA
        alias                   serverA and serverB
        hostgroups              your_hostgroup
        address                 serverA_ip
        _BADDRESS               serverB_ip
}
Service definition

Code: Select all

# LOAD CHECK
define service {
        use                             generic-service
        name                            serverB_Load
        service_description             serverB Load
        check_command                   check_serverB_load!7.2,5.6,4.8!8,6.4,5.6
        normal_check_interval           5
        notification_interval           10
        notification_options            w,c,r
        }

Re: service monitoring in dual fail over servers

Posted: Fri Jul 21, 2017 9:29 am
by tacolover101
as another side note, why not assign a VIP between your active / passive services and then monitor the VIP?

Re: service monitoring in dual fail over servers

Posted: Fri Jul 21, 2017 11:56 am
by dwhitfield
@padu_3891, did you have any other questions or are we ready to lock this up?