SNMP - ERROR: No response from remote host "IP"

[Shwele]

Heya fellas,

having issues with SNMP, so here is what I did and checked so far.

On nagios server I have installed SNMP so I have fresh software from there.
On server that I wanna track via SNMP I have installed it and configured it with following documentation on this link:
https://assets.nagios.com/downloads/nag ... g_SNMP.pdf
I have configured for v3.

When I try to run command (with proper IP ofc), I get this output:

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./check_snmp_storage.pl -H 10.25.13.37 -l nagios -x Str0ng@uth3ntic@ti0n -X Str0ngPriv@cy -L SHA,AES -m "^/$" -w 2 -c 4
ERROR: No response from remote host "10.25.13.37" during discovery.

snmpwalk output:

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snmpwalk -v 3 -c public -O e 10.25.13.37
snmpwalk: Timeout

Nmap works tho and shows that port is indeed open:

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[root@nagios libexec]# nmap 10.25.13.37 -p 161 -sU

Starting Nmap 6.47 ( http://nmap.org ) at 2017-11-01 13:57 CET
Nmap scan report for website.com (10.25.13.37)
Host is up (0.00041s latency).
PORT    STATE         SERVICE
161/udp open|filtered snmp

Nmap done: 1 IP address (1 host up) scanned in 0.32 seconds

162 port is closed, maybe it has to go over that port?

That is about it, hopefully someone can help me with this issue... @npolovenko winky face

Lastly will lay out some mistakes in documentation for you to edit.

On Debian / Ubuntu based systems use the following command:
sudo apt-get install snmpd libsnmp-dev

You need to add snmp too, for example I did not have it installed on server and didn't have conf file located in /var/lib/snmp/snmpd.conf

iptables -I INPUT -p udp –-destination-port 161 -j ACCEPT

Change to this for Ubuntu 16.04 -> iptables -I INPUT -p udp --dport 161 -j ACCEPT

[tgriep]

I have seen in the past when a nmap was run against a UDP Port and it says OPEN / filtered, it truly is not open but firewalled.
Please verify that the port is open and for a test, can you configure the device for SNMP v 2 and see if that works?

[Shwele]

You are correct. Seems like our hosting created new server on another network, using different subnet.
It was security issue and it could not be connected over SNMP.

That is why it was filtered, totally forgot that open/filtered meant its not opened for connections.

Tested it on another server, when we moved nagios server to proper network and it works now. We can close this now, thanks.