[RndTbl] Watching servers?

[Sydney Weidman]

On Thu, 2009-17-09 at 13:27 -0500, Kevin McGregor wrote:
> Hey all,
> 
> 
> Not actually UNIX related, but since a lot of you are network admins
> you might have some suggestions.
> 
> 
> I'd like to keep an eye on a bunch of servers (~20) but all I need to
> know is which ones are up or down, and if they're down, when they were
> last "seen". Does anyone know of a simple, free tool that will do
> that? I don't want details like number of packets lost or any such.
> Mostly I want to know which machines shut down and in what order.
> 
> 
> Thanks in advance,
> Kevin

I use Monit.

http://mmonit.com/monit/

Very simple configuration syntax with configurable alert parameters.
This example includes checking http service as well as ping. There is
also a web interface for checking the status of monitored entities,
which shows the "last seen" time, I believe. The "service detail"
screenshot shows it:

http://mmonit.com/monit/screenshots/monit_httpd1.html

check host foo with address 192.168.1.20
  if failed icmp type echo count 4 with timeout 15 seconds for 2 cycles
then alert
  if failed url
    http://your.server.com/path/to/whatever with timeout 15 seconds
    2 times for 2 cycles
    then alert
    alert **********@msg.telus.com
    alert **********@text.mts.net
    alert **********@text.mts.net
      only on { icmp, connection } 
      mail-format {
        from: someaddress at example.com
        subject: Foo Server $EVENT
        message: Monitoring Foo Server on $DATE
      }