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

Compare multiple server times to localtime


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


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


Try something like this:


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

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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