sshow: turn your ssh config into a catalog, ready to multiplex

You have ssh configuration on your machine that you use to access your favorite servers. You might even have a lot of servers scattered across different projects, with different naming schemes. sshow and its associated commands, nssh and nscp are here you help you navigate your ssh configuration and easily send one-off commands to groups of servers.

Installation

Install for your user

make install

Install system wide in /usr/bin

sudo make install

Install in developer mode (symlinks to files in this repo)

make install_dev

Usage

Let's say your ssh config looks something like this:

Host clientA-projecta-server1
Host clientA-projecta-server2
Host clientB-projecta-server1
Host clientB-projecta-server2
Host clientB-projectB-server1
Host clientB-projectB-server2
Host awesomeproject-server1

sshow by its self just shows your entire config

$ sshow 

clientA-projecta-server1
clientA-projecta-server2
clientB-projecta-server1
clientB-projecta-server2
clientB-projectB-server1
clientB-projectB-server2
awesomeproject-server1

Naturally, you can filter

$ sshow  server2

clientA-projecta-server2
clientB-projecta-server2
clientB-projectB-server2

grep can also filter, but you already knew that

Multiplexing with nssh

Simply pipe sshow to nssh which runs your command on all servers, sequentially. Note that aren't interactive shells, any interactive prompts will hang (think apt install without -y).

sshow server2 | nssh ls
clientA-projecta-server2
-------------------------------------
conf
nohup.out
.bashrc


clientB-projecta-server2
-------------------------------------
cruft.txt

....

nscp

Same thing for scp with nscp

sshow server2 | nscp my_file.txt

nscp will always scp to the home dir on the remote server. If you want something better, open an issue (or use ansible)

Timeouts

nscp and nssh timeout if the command takes more than 15 seconds to complete on the remote server, (or if the remote server does not respond) To alter this timeout, modify NSSH_TIMEOUT environment variable, or set the --timeout argument. A timeout of 0 equals no timeout.

sshow server2 | nssh ls --timeout 0 # will never timeout

Just SSH interactively into first result

If you want to just ssh into the first result, add the word go to the end of the command

$ sshow projectB go

sshing into clientB-projecta-server1...

...