H Forum,
I was thankful in getting help from this post that allowed me to connect to multiple severs at once using here documents to gather data into variables. But I've discovered that the same bash command that works on my RHEL 7 servers do not work on RHEL 6? What's strange about my problem is that I'm not getting an error either. The problem is that the variables return empty when I try the following code on RHEL 6.8 or 6.9 servers we manage:
IFS=$'\t' read FLAVOUR HOSTNAME ACTIVE_KERNEL INACTIVE_KERNEL UPTIME <<- EOFREAD
$ssh -qo StrictHostKeyChecking=no -o ConnectTimeout=1 user@$InputIP sudo -u user sh -s <<- EOFSSH | tr $'\n' $'\t'
exec bash
cat /etc/redhat-release 2>/dev/null || lsb_release -a 2>/dev/null | grep Description | cut -f2
awk -F= '/^NAME/{print $2}' /etc/os-release 2>/dev/null || grep Red |cat /etc/redhat-release 2>/dev/null || lsb_release -a 2>/dev/null | grep Description | cut -f2
hostname
uname -r
rpm -qa | grep '^kernel-[0-9]' |grep -vE `uname -r` | paste -sd \; || echo "Can't List Ubuntu Kernels"
uptime | cut -d "," -f1
exit
EOFSSH
)
EOFREAD
I've thought of adding in the ability to determine if my server is RHEL 6 or 7 using code like the following:
python -mplatform | grep -qi red &&
but even if I could determine RHEL version I'm still not sure why my RHEL 6 servers do not return variable data back. I've tested this above code connecting to just one server to try and triage the issue. No errors are returned. the variable fields are just empty. Whereas on my RHEL 7 servers I return back variables with no issue. Could it be that how I use Here Documents just doesn't work with RHEL 6 servers? has anyone seen this before?
I've also tested connecting to a RHEL 6 server multiple times to get the data I need. what I mean by this is instead of connecting to a RHEL 6 server once and collecting data I've tested connecting to a RHEL 6 for each command I need so connecting multiple times and there are no issues with the above commands I'm issuing.
Perhaps I'll just need to identify RHEL 6 servers and gather their data differently than I do for RHEL 7 severs but before I do that I thought I would check this forum for any advice first.
Thank you.