Usually I use network group to show a list of devices ordered by IP to show consumed IP and find free address to use on new devices on that network.
But IP addresses of manually added devices aren't visible in network group and I can't know which IP are free or anyway the network group is incomplete.
How I can solve the problem?
I'm quite sure the networks only look at data in the "ip" table. Manually populated devices do not have any entries in this table. I will need to check. I will advise when I have done so. FYI - I'm away from the keyboard until Tuesday next week. I'll advise ASAP after that.
Have confirmed that on 2.x, we only take into account the "ip" table - which a manually added device does not populate. I'll add a development ticket to see if we can't make that happen somehow.
My apologies for the delay. I just reread your question. Are you using a version pre 2.0?
Network Groups as such don;t exist post 2.0. We now simply have "Networks", which you can use to see the devices within.