====== Unix - Actively Monitor Multiple Logs ======
On Unix like systems, a handy method to monitor multiple logs simultaneously is combining [[https://linuxize.com/post/getting-started-with-tmux/|tmux]] and [[https://www.2daygeek.com/install-and-use-advanced-log-file-viewer-navigator-lnav-in-linux/|lnav]] (consult your OS for installing these utilities)

This example will actively monitor ''/var/log/syslog''; ''/sbbs/data/sbbsecho.log''; ''/sbbs/exec/umonitor''

=== setup tmux ===

First, setup [[https://linuxize.com/post/getting-started-with-tmux/|tmux]] to have 3 panes start with a bash script similar to:

  #!/bin/sh
  tmux new-session -s "Whatever Tmux" -d
  tmux split-window -v
  tmux split-window -h
  tmux -2 attach-session -d  

Once [[https://linuxize.com/post/getting-started-with-tmux/|tmux]] has started you'll see three panes each with a command prompt.  Depending on how your [[https://linuxize.com/post/getting-started-with-tmux/|tmux]] key bindings are setup,
(this example uses the default bindings CTRL+B+<arrow_key>) navigate to each pane and launch your desired app. 

== lnav/tmux panes ===

This example uses the top full width pane to monitor ''/var/log/syslog'' as it is the most verbose of our active monitoring:

  $ sudo lnav /var/log/syslog
  
Next, navigate to one of the split horizontal panes at the bottom of the window:

  $ lnav /sbbs/data/sbbsecho.log 
  
Lastly, navigate to the 3rd pane:

  $ /sbbs/exec/umonitor
  
You should now have 3 panes, each monitoring one aspect of you Synchronet BBS activity.

== example image ===

{{:monitor:basic-tmux.png?400|}} 

===== Advanced tmux example =====

In this example, we create a bash script that sets tmux up for us and automatically launches a few goodies:
  me@localhost: $ nano sbbsmux

  #!/bin/bash
  # sbbsMux - SBBS Monitoring script
  tmux new-session -d -s sess >/dev/null
  tmux rename-window -t sess:0 'AlleyCat'
  tmux splitw -v -p 20 -t sess:0.0
  tmux splitw -h -p 80 -t sess:0.1
  #required; otherwise pane numbering is bs
  tmux select-pane -t sess:0.0
  tmux splitw -h -p 5 -t sess:0.0
  tmux send-keys -t sess:0.0 'lnav' Enter
  tmux send-keys -t sess:0.2  'sudo htop -u pi' Enter
  tmux send-keys -t sess:0.1 '/sbbs/exec/umonitor' Enter
  tmux select-pane -t sess:0.0
  tmux new-window -t sess
  tmux rename-window -t sess:1 'BBS'
  tmux splitw -v -p 10 -t sess:1.0
  tmux splitw -h -p 80 -t sess:1.1
  tmux select-pane -t sess:1.0
  tmux splitw -h -p 10 -t sess:1.0
  tmux clock -t sess:1.1
  tmux new-window -t sess
  tmux rename-window -t sess:2 'Monitor'
  tmux splitw -v -p 10 -t sess:2.0
  tmux send-key -t sess:2.0 'lnav /sbbs/data/sbbsecho.log' Enter
  tmux select-pane -t sess:2.0
  tmux splitw -h -p 5 -t sess:2.0
  tmux clock -t sess:2.1
  tmux select-window -t sess:0.0
  tmux a -t sess

** note Edit 'tmux rename-window -t sess:x 'Accordingly' **

Save this as sbbsmux (or whatever) and chmod +x and launch it

  someone@somewhere: $ ./sbbsmux

The output should look similar to:

{{:monitor:sbbs-tmux-sbbsecho1.png?400|}}

Navigate to the pane with the prompt, this was left available to preforming tasks.  Here we will launch another monitoring tool:

  me@mynixbox: $ lnav /sbbs/data/sbbsecho.log
  
Now we should see something similar to:

{{:monitor:sbbs-tmux-sbbsecho.png?400|}}






===== See Also =====
  * [[:monitor:|monitor index]]

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