What's a good definition of Link-Status ?

[getwithrob]

I'm trying to write a small proposal for the customer which deals directly with link-status messages sent from Cisco switches.

Link-status messages can be sent to logging and sent via SNMP to the trap destination address.

The commands:

logging event link-status

no logging event link-status

snmp trap link-status

no snmp trap link-status

are used to turn these messages on and off on each interface/switch port.

I'd like to start this write up by giving a good definition of Cisco's link-status and exactly what it does and maybe doesn’t do.

Thanks.

[nhabib]

If you enable them, then you will receive notification when the link-status transitions from up to down (and vice versa).

Basically if link-status is up, then you are able to communicate. If link-status is down, then you are unable to communicate.

[getwithrob]

Understood.

I'm looking for a text book or formal definition that might be found in a dictionary. A Cisco dictionary definition perhaps....

[nhabib]

Interesting. Not sure I've run into an official definition on the Cisco site. It may be in some RFC on the IETF's site.

[pkhatri]

Here's a definition from RFC2863 (The Interfaces Group MIB):

"A linkDown trap signifies that the SNMP entity, acting in an agent role, has detected that the ifOperStatus object for one of its communication links is about to enter the down state from some other state (but not from the notPresent state). This other state is indicated by the included value of ifOperStatus."

"A linkUp trap signifies that the SNMP entity, acting in an agent role, has detected that the ifOperStatus object for one of its communication links left the down state and transitioned into some other state (but not into the notPresent state). This other state is indicated by the included value of ifOperStatus."

Hope that helps - pls rate the post if it does.

Paresh

[pkhatri]

Just another note...

RFC2863 provides the official definition of the ifMIB which is supported as a standard by just about every vendor out there.

It was co-authored by a Cisco person ...

Paresh