notes: Frame Relay End-to-End Keepalives

Adds the ability to track status between DTE devices.
- Freek can be configured on a physical interface, but when the freek status goes down, freek will not bring down the physical interface, because it will not know when to bring it back up.
- For this reason it is recommended to configure freek on a sub-interface.

Freek Modes:

1. Bidirectional

- Both sides of the PVC can send and respond to keepalive requests.
- If one side is configured as bidirectional, the other end must be configured the same.
- Sets the timers and keeps track of error counters.

2. Request

- With Request mode only one side is enabled in send mode.
- If one side is configured as Request, the other end must be Reply or Passive-Reply.
- Sets the timers and keeps track of error counters.

3. Reply

- The device waits for, and replies to keepalive requests.
- If one side is configured as Reply, the other end must be Request.
- Sets the timers and keeps track of error counters.

4. Passive-reply
- The device waits for keepalive requests and responds to them.
- Sets the timers.

example:

configure end-to-end keepalives for the VC. if the routers have 3 errors within 4 events. the subinterface should transition into down state. and if they have 4 success events in a row, the sub-interface should transition into up state. ensure that keepalivs are exchanged every 20 seconds.

config-set:

map-class frame-relay TST14
frame-relay end-to-end keepalive mode bidirectional
frame-relay end-to-end keepalive timer send 30
frame-relay end-to-end keepalive timer recv 20
frame-relay end-to-end keepalive event-window send 5
frame-relay end-to-end keepalive event-window recv 5
frame-relay end-to-end keepalive error-threshold send 3
frame-relay end-to-end keepalive error-threshold recv 3
frame-relay end-to-end keepalive success-events send 4
frame-relay end-to-end keepalive success-events recv 4
!
interface Serial0/0.104 point-to-point
ip address 150.1.14.1 255.255.255.0
frame-relay interface-dlci 104
class TST14