Script to find Error: rpmdb open failed on list of servers

Shell Programming and Scripting
1

Hello all,

I have a task to patch red hat servers and some servers have a corrupted rpm database and return the error:

Error: rpmdb open failed

I know how to fix this when it occurs. What I'm hoping to do is scan a list of servers by IP and report back which server have this error.

Would someone be able to assist or point me in the right direction on how I capture this? My thought is to run the following:

sudo yum update infolist

On each server and capture the output to find the error.

Thanks in advance for any assistance or pointers you can provide me.

2

Are you considering to run your "status checking" script in cron?

3

You can use a for loop and process substitution and some descriptor magic:

#!/bin/bash
for server in server1 server2
do
  ssh -x "$server" '
    echo "hello I am on `hostname`"
    sudo yum update infolist
  ' 2> >(sed "s/^/$server: /" >&3)
done 3>stderr

The stderr output goes to the file stderr, filtered by sed.
The sed prepends $server: to every stderr line. It can also prepend it once:

for server in server1 server2
do
  ssh -x "$server" '
    echo "hello I am on `hostname`"
    sudo yum update infolist
  ' 2> >(sed "1i\\
$server:" >&3)
done 3>stderr
4

Hello @MadeInGermany and @Neo,

Thanks very much for your replies.

My intention is not to use this in a cronjob.

The script that MadeInGermany is what I was looking for. When I run these scripts I receive the following errors:

First Script Error:

 
checkyum.sh: line 7: syntax error near unexpected token `>'
checkyum.sh: line 7: `  ' 2> >(sed "s/^/$server: /" >&3)'

Second Script Error:

 
checkyum.sh: line 7: syntax error near unexpected token `('
checkyum.sh: line 7: `  ' 2>>(sed "1i\\'

My BashFu is pretty weak. Would you be able to point out what I need to change to get this working?

thank you.

5

For using the <( ) and >( ) process substitution, the OS must support Unix devices, and bash must be compiled to utilize it.
Obviously not true for your OS and bash.?

uname -sr
bash --version

The following pipes stderr (descriptor 2) to sed. But a pipe works with stdout (descriptor 1) only. Therfore, it swaps stdin and stdout before the pipe, and afterwards swaps them back.

#!/bin/bash
for server in server1 server2
do
  {
  ssh -x "$server" '
    echo "hello I am on `hostname`"
    sudo yum update infolist
  '  3>&2 2>&1 1>&3 | sed "s/^/$server: /" 
  } 3>&2 2>&1 1>&3
done 2>stderr
6

Hello @MadeInGermany,

Apologies for not responding sooner to your helpful reply.

Here are some details of the Red Hat server I'm using:

$ uname -sr
Linux 3.10.0-1062.el7.x86_64

$ bash --version
GNU bash, version 4.2.46(2)-release (x86_64-redhat-linux-gnu)

I'm trying my hand at this script again. I've used your suggestion:

#!/bin/bash
for server in server1 server2
do
  ssh -x "$server" '
    echo "hello I am on `hostname`"
    sudo yum update infolist
  ' 2> >(sed "1i\\
$server:" >&3)
done 3>stderr

I can successfully login to a server and I receive the echo that says "hello I am on 'hostname'" so the script is working and gives me this detail back. But I don't receive any other data back after running this script against my test server? Would this be the result if rpmdb open failed wasn't occuring on this test server? What I mean is...will the above script only show if rpmdb open failed exists and if it doesn't the script returns nothing back?

Thank you.

7

Here is an example of what I'm trying to do. If someone can help me formulate this line properly to get what I need please:

Code:

sudo yum repolist | grep -qi 'Error: rpmdb open failed ' ; case "$?" in "0") echo "Match" ;; "1") echo "No Match" ;; *) echo "Error" ;; esac

I would like to use a one line command so use it in a bash script along with other checks I do.