bash,shell,date,time,scripting , Compare multiple server times to localtime


Compare multiple server times to localtime

Question:

Tag: bash,shell,date,time,scripting

I am looking to compare x amount of server times to a control local time(current time at the running of the script) to check if any of the servers are out of sync with the current time. If the servers are more than a few seconds behind then throw and error message.

This is what I have so far

#!/bin/sh

servers="server1.... server2...."
now="date +%s"
for server in $servers
do
  ssh -l root ${server} "date +%s"
  if [ $? -eq "$now" ] ; then
    echo $server - IN SYNC
  else
    echo $server - NOT IN SYNC 
  fi
done

Answer:

Try something like this:

#!/bin/bash

servers="server1.... server2...."
seconds="3"  # value for servers to differ (in seconds)
for server in $servers
do
    difference=$(echo $(ssh -l root ${server} "( date +%s )") "-" $(date +%s) | bc)
    if [[ ${difference#-} -le ${seconds} ]] ; then
        echo $server - IN SYNC
    else
        echo $server - NOT IN SYNC 
    fi
done

I've given the script in pseudo code-ish, along the same lines you've given yours (I have switched to bash though).


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