Commands by rxw (2)

  • Keep SSH tunnel open (PostgreSQL example)

    Check if SSH tunnel is open and open it, if it isn't. NB: In this example, 3333 would be your local port, 5432 the remote port (which is, afaik, usually used by PostgreSQL) and of course you should replace REMOTE_HOST with any valid IP or hostname. The example above let's you work on remote PostgreSQL databases from your local shell, like this: psql -E -h localhost -p 3333


    -1
    while true; do nc -z localhost 3333 >|/dev/null || (ssh -NfL 3333:REMOTE_HOST:5432 USER@REMOTE_HOST); sleep 15; done
    rxw · 2015-09-21 02:25:49 11
  • Alert on high ping to know if it's really laggy while playing

    Online games have pretty good lag compensation nowadays, Sometimes though, you really want to get some warning about your latency, e.g. while playing Diablo III in Hardcore mode, so you know when to carefully quit the game b/c your flatmate started downloading all his torrents at once. This is done on Darwin. On Linux/*nix you would need to find another suitable command instead of `say` to spell out your latency. And I used fping because it's a little bit easier to get the latency value needed. Something similar with our regular ping command could look like this: while :; do a=$(ping -c1 google.com | grep -o 'time.*' | cut -d\= -f2 | cut -d\ -f1 | cut -b1-4); [[ $a > 40 ]] && say "ping is $a"; sleep 3; done


    1
    while :; do a=$(fping -e google.de | grep -o '[0-9]+.[0-9]+'); [[ $a > 40 ]] && say "ping is $a"; sleep 3; done
    rxw · 2015-09-21 02:14:02 51

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