Can someone explain what these arguments mean?

Hi folks,

I am betting this is a very simple thing, but I admit i don't know the proper terms to search it out correctly.

I am self-learning at work.
I've come on a section of code in a script:
What I can't figure out(or search out) is what the arguments "5 2 2>&1" are doing??

I thought it was setting 2 '5 byte messages' with a time to live of 2...something.
But I can not find any data to support that or otherwise explain what's going on here.

So thanks to anyone who can explain this.

Marc