Identifying free ports on Cisco Switches

I want to tell what ports are available on a Cisco switch... would it be safe to use "show interfaces counters" if the switch has been up for a long time and use the ports that show 0-1000 packets/bytes of throughput?  Most of the ports are in the billions+  and several are at 0.. but there are some at 1000 and I was "guessing/assuming" that those ports are just noise?

Or is there a better way to identify free ports so we can tell what is/isn't used rather than just looking at plugged in cables that never have been removed?

A friend just suggested "show int summary" and to go by the asterisks THEN by the counters...
Anyone have any better ideas or is that a pretty thorough way to handle it?

Thank you in advance!

Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Todd GerbertIT ConsultantCommented:
sh int | include line proto
"show interfaces" should tell you if the line protocol is up or down (i.e. connected or not), "| include line proto" just filters the results.
show int status | include notconnect


show interfaces summary | exclude \*
"show interfaces status" will show you if a port is connected or not. That will give you if there is a device on the other end. But with this it could mean that the device on the other end is shutdown or the cable is unplugged. So not 100%

Use this to see which ports are active then use "sh int counters" on the disconnected or downed ports to see if there is any recent traffic on those ports.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Become an IT Security Management Expert

In today’s fast-paced, digitally transformed world of business, the need to protect network data and ensure cloud privacy has never been greater. With a B.S. in Network Operations and Security, you can get the credentials it takes to become an IT security management expert.

och1Author Commented:
That command will tell me if the port is up RIGHT NOW... but it doesn't help me with a "historical perspective" what if that is a port of someone in accounting that is on vacation or out of the office this week?
I need something that provides a little more "guarantee"....  (I have 40+ switches and 700-ish users/nodes across 13+ locations) and want to find out if we really need more hardware or just need to better utilize the ports that "we don't know we have")
We are definitely not a big network (just spreadt out), and as such, we have to be really careful with expenditures (and save the money for important things like my Experts-exchange membership!!!) :)
och1Author Commented:
thank you guys, it took me long enough to respond to the first comment I hadn't read the rest of them yet!
och1Author Commented:
I choose this as the "complete" solution because:
After doing the other solution(s) like the one containing "exclude \*" and comparing the results on a "port per port" basis the "exclude \*" solution misleads you in to thinking all of those ports have not been in use for quite awhile.. until you run "show int counters" and compare all the in/out packets and realize that something has recently talked on that port.
Thank you all for your insight.. each of you (even the answers I DIDN"T pick) have shared knowledge with me that I didn't previously have.

How about: show int summary | include       0     0    0     0     0    0     0    0    0
using however many zero's you have on your counter line.

You can use rlogin app from RANCID package ( to automatically grab the output and dump to text file if your familiar with Linux.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Network Operations

From novice to tech pro — start learning today.