Editing ExecuteInAllVEs

I found myself often faced with a need to run the same command in all VEs, e.g. ''apachectl restart'' to restart all webservers or ''dmesg | tail'' to see the latest news from everybody.

At its core is just this simple tidbit: a for loop around vzlist.
<code>
  for veid in `vzlist -Hoveid`; do vzctl exec $veid COMMAND; done 
</code>

Knowing this, you can also save some typing later by making a simple utility out of it.
I like to call this ''/usr/sbin/vzexec'' so I can later just say ''vzexec apachectl restart''
<code>
  #!/bin/bash
  # vzexec -- execute a command on all VEs
  if [ "$1" == "" ]; then
    echo "$0 -- Execute a command on all VEs"
    echo ""
    echo "Example: vzexec service httpd restart"
    echo ""
    echo "Note that variables are expanded in the host's shell, and use ' ' to prevent this."
    echo "Example:   vzexec echo \$PWD    and   vzexec 'echo \$PWD'   are different."
    exit
  fi
  for veid in `vzlist -Hoveid`; do
    echo "*** VE $veid"
    vzctl exec $veid $@
  done
</code>