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I have several linux devices connected to the same router (of which I am not a administrator). How can I find out the ip addresses of all other devices by executing some commands in one of them?

qed
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  • related (with links to a lot of duplicate quesions): [How can I list all IPs in the connected network, through Terminal preferably?](http://superuser.com/q/261818/210781) – Alexander Malakhov Oct 22 '16 at 09:24
  • If this is a router and not a switch, I'm not sure if you can. A router doesn't pass broadcasts by default, and each device might be on a different subnet, so arp/nmap/fing/ping might be useless. – Dani_l Dec 16 '18 at 11:19

2 Answers2

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I believe you could use nmap to get such information.

The below command lists me all the machines/devices connected in my network. It is a home network and it lists me all the machines in my home. 

nmap -sP 192.168.1.0/24

I believe you need to modify the subnet mask and IP range that you are in to suit your requirements.

Ramesh
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    why 192.168.1.0/24? what means? – Tarlo_x Nov 07 '15 at 13:15
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    `nmap -sA 192.168.1.0/24` nmap option `-sA` shows similar descriptive results with better readability, which includes device name, IP, mac, etc as with option `-sP`. I personally prefer `-sA` over `-sP` for the readability sake. – Jay Feb 03 '16 at 10:17
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    @Tarlo_x https://superuser.com/questions/970380/so-what-does-24-have-to-do-with-255-in-hosts-ip-addresses – Alessandro Jacopson Sep 02 '18 at 09:30
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For a more compact list of connected devices:

nmap -sL 192.168.0.* | grep \(1

Explanation
nmap -sL 192.168.0.* will list all IPs in subnetwork and mark those, that have name: 

Nmap scan report for 192.168.0.0
Nmap scan report for Dlink-Router.Dlink (192.168.0.1)
Nmap scan report for 192.168.0.2
...
Nmap scan report for android-473e80f183648322.Dlink (192.168.0.53)
...
Nmap scan report for 192.168.0.255

As all interesting records contain parenthesis ( and digit 1, we filter for that with | grep \(1 (backslash is needed to escape parenthesis)

Quirk
Beware that if two devices have the same name, nmap will show only the one, that was connected to router last

Alexander Malakhov
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