External monitoring from the inside?

Posted on 2007-10-01
Last Modified: 2010-04-17
We recently ran into a small item of note on our network and we are looking for a way to mitigate the problem. I have an good idea of what we could do but wanted to see if anyone else had a better solution.

Here's the scenario:

We run OpManager 7 internally (internal IP scheme). We need to be able to monitor a website from the outside (external NAT IP). I know you can't physically loopback traffic on the same interface or at least we are not setup to do so at this time. Does anyone have any ideas?

My theory is to open a switchport on an isolated DMZ to all ICMP echo (or other OPMAN protocol?) traffic but it does open a gaping hole in our network and puts our server/software at risk.

All servers and user workstations are on separate vlans behind the firewall.

Question by:technowonder
    LVL 4

    Accepted Solution

    I can think of two options:-
    1) use an external (e.g. internet) proxy to run the URL check through (dependant on your software being able to accept a proxy for this website only)
    2) use a second internet connection (e.g. cheap ASDL/DSL connection) to run this specific website test - you'll need to add routes to the monitoring server/PC to force it to go out this second internet connection.

    Best of luck!
    LVL 4

    Expert Comment

    Hi technowonder, any update on your issue?
    LVL 2

    Author Comment

    Yes, we're still mulling the issue over and looking for alternatives. Thanks for your suggestions.
    LVL 1

    Expert Comment

    Forced accept.

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