I need to write a script to find total memory and total swap of several linux server (2000+). I have one trusted server from where I can login to all these 2000 servers without a password.
When I run this script, it should give output like this:
Server total memory swap
redhat1
redhat2
redhat3
...
redhat2000
How can I achieve this?
The /proc/meminfo file contains the information you're after. It's pretty easy to parse too.
This will get you the RAM and swap (in that order, unit is kB on all systems I know):
awk '/^(MemTotal|SwapTotal)/{print $2}' /proc/meminfo
To format it, you could do something like:
printf "%s\t%d\t%d\n" $(hostname) \
$(awk '/^(MemTotal|SwapTotal)/{print $2}' /proc/meminfo)
To combine that with ssh, do something like:
for host in your_list_of_servers ; do
printf "%s\t%d\t%d\n" $host \
$(ssh $host "awk '/^(MemTotal|SwapTotal)/{print \$2}' /proc/meminfo")
done
First You need to setup password less log-in, you can refer this page .
After that you can use below script as per your requirement.
#!/bin/bash
# store username:ip combo here separated by a whitespace
_pair="[email protected] [email protected] [email protected]"
for e in $_pair
do
# extract user and ips for each $e in $_pair
IFS='@'
set -- $e
_user="$1"
_ip="$2"
sleep 2
echo "Connecting to server '${_ip}' via SSH..."
ssh ${_user}@${_ip} "free -m | awk -v h=$HOSTNAME '(/Mem/||/Swap/){printf("%s\t%s%d\t",h,$1,$2)}'; echo -e"
done
