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nitefood/multitail.sh

Last active March 28, 2023 09:07
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Revisions

  1. nitefood revised this gist Dec 3, 2020. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion multitail.sh
    View file
    Original file line number Diff line number Diff line change
    @@ -15,7 +15,7 @@ for host in $hostlist; do
    # establish ssh connection to the hosts and launch the remote command
    # use colored hostname prefix for every logline to clearly highlight the host where the log line is from
    remote_command='tail -f '"$remote_logfile"' | while read logline; do printf "\e[38;5;'"$((1+$RANDOM%228))"'m%-25s\e[0m $logline" "[$HOSTNAME]"| grep -E "'"$search_pattern"'"; done'
    ssh $user@$host "$remote_command" 1>tailpipe 2>/dev/null & # launch the ssh command
    ssh $user@$host "$remote_command" 1>"$HOME/tailpipe" 2>/dev/null & # launch the ssh command
    [[ -n "$children" ]] && children+=" $!" || children+="$!" # save the ssh child PID in order to clean it up at ctrl-c time
    done

  2. nitefood created this gist Dec 3, 2020.
    22 changes: 22 additions & 0 deletions multitail.sh
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,22 @@
    #!/usr/bin/env bash

    # ssh targets and log search pattern
    user="root" # remote ssh user
    hostlist="host1.example.com host2.example.com host3.example.com" # space-separated ssh hosts list
    remote_logfile="/var/log/syslog"
    search_pattern="Session" # can use regexps here (grep -E)

    # trap ctrl-c for named pipe cleanup and ssh process killing
    trap 'echo -e "\n\nCleaning up..."; for pid in $children; do kill -9 $pid 2>/dev/null; done; rm "$HOME/tailpipe"; exit 0' INT

    mkfifo "$HOME/tailpipe" # create named pipe to read remote tail output from
    children=""
    for host in $hostlist; do
    # establish ssh connection to the hosts and launch the remote command
    # use colored hostname prefix for every logline to clearly highlight the host where the log line is from
    remote_command='tail -f '"$remote_logfile"' | while read logline; do printf "\e[38;5;'"$((1+$RANDOM%228))"'m%-25s\e[0m $logline" "[$HOSTNAME]"| grep -E "'"$search_pattern"'"; done'
    ssh $user@$host "$remote_command" 1>tailpipe 2>/dev/null & # launch the ssh command
    [[ -n "$children" ]] && children+=" $!" || children+="$!" # save the ssh child PID in order to clean it up at ctrl-c time
    done

    cat < "$HOME/tailpipe" # read remote log lines from the named pipe