Every now and again you see a snippet of complex CLI syntax that gives you pause for thought. Last week I saw the command below in a change procedure. The command was being used to verify baseline BGP neighbor state and re-verify after a policy change.
1 2 3
show ip bgp peer-template eBGP_Peers | egrep default | sed 's/default://' \ | tr -s ' |\n' | tr -s ' ' '\n' | sed 's/^/show ip bgp nei /' \ | sed 's/$/ adver | grep \//' | vsh
I was a little daunted by the complexity of the command at first. I was slightly embarrassed too, as I had no idea what the command did. I learned that this command finds all neighbors which use a named bgp peer-template, and lists the prefixes they advertise. In this post I’ll break down the command and share the love about NXOS CLI and bash scripting. Continue reading