IOS versions

Warning, newbie question soon to follow!!!

I'd like to get some clarification on IOS types. Cisco routers use IOS. But do all switches use CatOS? Or is that an old OS that is being replaced now by regular IOS? And if so, is the IOS and it's commands pretty much similar to router IOS? What about Layer 3 switches? I assume those are using router IOS?

What about PIX and ASA firewalls? Are they using another type of IOS?

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Comments

tiersten

notgoing2fail wrote: »

Cisco routers use IOS.

Apart from some ancient routers but generally yes, all Cisco routers use IOS of some kind. There is the plain monolithic IOS which is in most hardware and then there are the modular ones like IOS-XR and IOS-XE which tend to be in the very high end hardware only.

notgoing2fail wrote: »

But do all switches use CatOS? Or is that an old OS that is being replaced now by regular IOS?

CatOS in switches was replaced by IOS. Some old switches are stuck with CatOS. Some could be upgraded to IOS. Some could work in a hybrid configuration where part of it ran CatOS and another part ran IOS.

notgoing2fail wrote: »

And if so, is the IOS and it's commands pretty much similar to router IOS?

Similar. Not quite 100% since it is a different branch of IOS.

notgoing2fail wrote: »

What about Layer 3 switches? I assume those are using router IOS?

Still the switch version of IOS.

notgoing2fail wrote: »

What about PIX and ASA firewalls? Are they using another type of IOS?

Not IOS but with an IOS like CLI in newer versions. Old versions weren't IOS like. All PIX boxes and the blade use Finesse. Newer PIX/ASA OS versions on an ASA run on top of a Linux kernel.

notgoing2fail

Thanks tiersten,

I knew out of all people you might be the one to respond regarding IOS's...

Interesting that the ASA's run on top of a linux kernel, that is extremely interesting to me since I come from the LAMP world... (linux, apache, mysql, php)...

chmorin

In my network at work we have a few switches still using CATOS. I have gotten pretty good at working with them, but half the stuff is just... stupid. SET commands suck.

notgoing2fail

chmorin wrote: »

In my network at work we have a few switches still using CATOS. I have gotten pretty good at working with them, but half the stuff is just... stupid. SET commands suck.

SET commands? wow....sounds like Juniper....

Stotic

I find catos to be very convenient with certain commands and down right horrible with others.

I love being able to do sh port X and receive all the ports on that card and naming just consists of set port x/x blah rather than going into the interface.