Dell Force10 S4810P Configuration Manual page 144

4. The passive system receives the control packet, changes its state to Up. Both systems agree that a
session has been established. However, since both members must send a control packet—that requires
a response—anytime there is a state change or change in a session parameter , the passive system sends
a final response indicating the state change. After this, periodic control packets are exchanged.
ACTIVE System
Version: 1
Diag Code: 0 (assumes no previous session)
State: Up
Flag: P: 1
Detect Multiplier: User-configurable
My Discriminator: X
Your Discriminator: Y
Desired Min TX Interval: User-configurable
Required Min RX Interval: User-configurable
Required Min Echo RX Interval: User-configurable
Version: 1
Diag Code: 0 (assumes no previous session)
State: Up
Flag: P: Clear
Detect Multiplier: User-configurable
My Discriminator: X
Your Discriminator: Y
Desired Min TX Interval: User-configurable
Required Min RX Interval: User-configurable
Required Min Echo RX Interval: User-configurable
Session state changes
The illustration below shows how the session state on a system changes based on the status notification it
receives from the remote system. For example, if a session on a system is down, and it receives a Down
status notification from the remote system, the session state on the local system changes to Init.
144
| Bidirectional Forwarding Detection (BFD)
Default Session State: Down
Steady Rate of Control Packets
current session state
the packet received
Down
Admin Down,
Timer
Down
Init
Version: 1
Diag Code: 0 (assumes no previous session)
State: Down
Flag: P:1
Detect Multiplier: User-configurable
My Discriminator: X ( Active System Session ID)
Your Discriminator: 0
Desired Min TX Interval: User-configurable
Required Min RX Interval: User-configurable
Required Min Echo RX Interval: User-configurable
Init State Change
Up State Change
Up State Change
Periodic Control Packet
Up, Admin Down, Timer
Init
Down
Admin Down,
Down,
Timer
Init, Up
Transmit Interval: User-configurable
Default Session State: Down
PASSIVE System
Version: 1
Diag Code: 0 (assumes no previous session)
State: Init
Flag: F: 1
Detect Multiplier: User-configurable
My Discriminator:
Your Discriminator:
Desired Min TX Interval: User-configurable
Required Min RX Interval: User-configurable
Required Min Echo RX Interval: User-configurable
Version: 1
Diag Code: 0 (assumes no previous session)
State: Up
Flag: F: 1
Detect Multiplier: User-configurable
My Discriminator: Y
Your Discriminator: X
Desired Min TX Interval: User-configurable
Required Min RX Interval: User-configurable
Required Min Echo RX Interval: User-configurable
Up, Init
Up
fnC0037mp
Y (Passsive System Session ID)
X
fnC0036mp