I have a LAN with 2 ranges of IP#'s: 192.168.0.xxx * & 192.168.1.xxx (2 routers). Besides that, there's 2 other routers, switches and a couple of PC's/laptops, tablets - all running different OS's. (There's no server as such)

I'm trying to do an autodiscovery of the network using software on one of the Ubuntu PC's on the network.

I'm being asked for the "SNMP Community String"

What's this and how and from where do I get it?

Would really appreciate some help on this, pls.

Spell out your words, please.

The SNMP community string on appliances (switches, routers, etc.), is usually pre-set at the factory, and can typically be found in the manual for the device. PC's and such need a bit more, since most 'consumer' units ship either without SNMP running or configured. For Linux systems, the string can usually be found in /etc/snmpd.conf. Not sure where Windows keeps such things, or how to configure them there.

And bear in mind that there are typically TWO strings....a 'public' string, which will let folks query the device, and a 'private' string, which will let folks do things to the device. Things like rebooting, configuring different aspects of the system, etc. An off-the-shelf guess would be that you're looking for the 'public' string, which is typically just "public"....and the private string would be (wait for it...) "private".