How to monitor remote servers and network devices?

[yancy]

Arnel,

You can use active checks against any host that you can reach from the Nagios machine. The easiest way would be to use a "Quick scan" to see which hosts can be contacted. You may need to edit the firewall rules on the remote hosts however.

-Yancy

[Noctis0791]

Thanks guys. I ran a quick scan on a remote host and I got this result.

Starting Nmap 6.40 ( http://nmap.org ) at 2013-10-17 14:40 Pacific Daylight Time
Nmap scan report for host.domain.com (Host IP)
Host is up (1.1s latency).
All 100 scanned ports on host.domain.com (Host IP) are filtered
Nmap done: 1 IP address (1 host up) scanned in 31.55 seconds

What does this line means "All 100 scanned ports on host.domain.com (Host IP) are filtered"? May I also know the specific ports used by NCPA and NSClient++ so that I can open these ports on the firewall when needed? Appreciate your help and patience guys.

Thank You,

Arnel

[yancy]

It means you only scanned one host. Take a look at the following:
http://nmap.org/bennieston-tutorial/

NCPA uses port 5693
NSClient++ uses 5666 or 5667

-Yancy

[Noctis0791]

Cool! Thanks. So I can also do the same test for remote network devices to see if we can run active checks on them?

Arnel

[slansing]

By network devices what do you mean? If you are talking about switches/routers we typically see others running SNMP checks to them which would primarily use port 161 TCP/UDP.

[Noctis0791]

Thanks guys. I will ping you again when I have further concern regarding this topic.

Thank You,

Arnel

[slansing]

Sounds good, we'll keep the thread open for now!

[Noctis0791]

Hello Guys,

What Nagios agent works best if we would like to monitor servers from different client domains? Let say just Windows servers for now and we would like to use our own Nagios server to monitor them.

We’ve tried to use NSClient++ and it seems that we would need to do NATting/Port forwarding first on the client side if we are going to monitor them (the servers) remotely. Is there a better agent we can use for this case or a better approach we could go into to avoid these extra works? Any idea or suggestion?

Thank You,

Arnel

[abrist]

Before we go down the rabbit hole of proxied checks, is a vpn/tunnel an option? If so, it is definitely the easiest as it would allow the nagios configuration to be rather agnostic about the topology . .

[Noctis0791]

Thanks abrist. We have a Juniper-SSG firewall. So what do you think would be the best approach to what type of VPN tunnel should we use for multiple clients that are on different networks? As we ask this question, we are looking at the following links for reference.

http://www.skullbox.net/vpn.php
http://vpncreative.net/quick-insight-di ... protocols/

Thanks again,

Arnel