How to tell how many external IP's we're using?

My company has a small block of IP's. I think we're using 4 of them, but I don't know which ones. Is there a way to tell how many external ones we are using and which ones are free?

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Comments

nice343

login into the router/firewall depending on which one you are using to get on the internet ASSUMING YOU KNOW WHAT YOU ARE DOING.

or another option is to ASK them

seuss_ssues

you can always perform a whois on one of your known public IP addresses and it should show you the range. Then possibly just do a ping sweep through that range and see whats active. The ping sweep will only show active devices that are not filtering ICMP messages so it could miss some. You can also log into whatever router/firewall that is connecting you to the internet and go through its settings.

seuss_ssues

nice343 wrote:

login into the router/firewall depending on which one you are using to get on the internet ASSUMING YOU KNOW WHAT YOU ARE DOING.

or another option is to ASK them

We dont always know what we are doing. Thats why there are places like techexams.net and google to help us find out.

Trailerisf

Call your ISP to find out which ones are assigned to you. They will also tell you which ones are registered and live.

Only sure way of knowing... (Well there are others, but I am lazy.)

Luckycharms

Firewall or IOS router (firewall image) ... or what kind of external gateway are you using... Might give us something to go on ..

(Honestly calling your ISP and asking what IP's are currently begin used is the meanest thing you guys could have told this person to do... If you have ever spent any time on the phone with an ISP trouble shooting any problems you know the hell that you have to go through... granted they can tell you what IP's you have registered to you, they more then likely won't spend the time finding out which ones are active. ) ( and an active whois... come on...) ( just tell the person to give more information. )

Just my 2cents

snadam

Trailerisf wrote:

Call your ISP to find out which ones are assigned to you. They will also tell you which ones are registered and live.

Only sure way of knowing... (Well there are others, but I am lazy.)

That should be Option #1. You really should have this IP info documented on site somewhere. If you cant find it on site, then call your ISP and get that info. Then keep it on site in a secure area. If your paying for a addy pool, then you should know what it consists of. A 10 minute call should solve the issue.