I tend to run the same SNMP probes on multiple devices quite often. The devices are always the same, the OIDs change. To simplify this I created a small Python script running the commands in a tmux session.
However, there seems to be a small bug/annoyance in tmux which makes it nearly impossible to run a command with special characters in it's parameters directly via tmux. Instead, "injecting" the keystrokes into the running session works fine.
I started off writing this in bash, but due to the issue mentioned above, I ended up writing it in Pythong, making the code a lot cleaner. Albeit unnecessary:
#!/usr/bin/python3 ''' Run "snmpwalk" on multiple devices simultaneously in separate tmux tabs. ''' from collections import namedtuple from os import environ from subprocess import check_call as run import sys environ['TERM'] = 'xterm-256color' # Hint for tmux to enable 256 colours. Connection = namedtuple('Connection', 'ip, community, name') TMUX_NAME = 'snmpt-probe' TARGET_DEVICES = [ Connection('1.2.3.4', 'helloworld', 'Device 1'), Connection('1.2.3.5', 'helloworld', 'Device 2'), Connection('1.2.3.6', 'helloworld', 'Device 3'), Connection('1.2.3.7', 'helloworld', 'Device 4'), ] def exec_(ip, oid, community): ''' Run a command using ``tmux send-keys``. This is a workaround. Executing the command directly does not work if a parameter contains special characters. ''' run(['tmux', 'send', '-t', TMUX_NAME, ' snmpwalk -v2c -c "']) run(['tmux', 'send', '-t', TMUX_NAME, community]) run(['tmux', 'send', '-t', TMUX_NAME, '" %s %s | less' % (ip, oid)]) run(['tmux', 'send', '-t', TMUX_NAME, 'ENTER']) def main(): # Ask the user to enter the OID oid = input('OID: ').strip() if not oid: print('OID cannot be empty!', file=sys.stderr) return 1 # Create a new, empty tmux session run(['tmux', 'new', '-s', TMUX_NAME, '-d']) # give the first window it's proper name run(['tmux', 'rename-window', '-t', '0', TARGET_DEVICES[0].name]) # create the remaining tabs with appropriate names for _, _, name in TARGET_DEVICES[1:]: run(['tmux', 'new-window', '-n', name]) # run the snmpwalk commands for ip, community, name in TARGET_DEVICES: run(['tmux', 'select-window', '-t', name]) exec_(ip, oid, community) # Attach the tmux session run(['tmux', 'attach', '-t', TMUX_NAME]) return 0 if __name__ == '__main__': sys.exit(main())Comment