Configuring The Ike Nat Keepalive Function; Configuring Ike Dpd - HP 6125XLG Configuration Manual

Configure IKE DPD instead of the IKE keepalive function unless IKE DPD is not supported on the peer.
•
The IKE keepalive function sends keepalives at regular intervals, which consumes network
bandwidth and resources.
• The keepalive timeout time configured at the local must be longer than the keepalive interval
configured at the peer. Since it seldom occurs that more than three consecutive packets are lost on
a network, you can set the keepalive timeout three times as long as the keepalive interval.
To configure the IKE keepalive function:
Step
1. Enter system view.
2. Set the IKE SA keepalive
interval.
3. Set the IKE SA keepalive
timeout time.

Configuring the IKE NAT keepalive function

If IPsec traffic passes through a NAT device, you must configure the NAT traversal function. If no packet
travels across an IPsec tunnel in a period of time, the NAT sessions are aged and deleted, disabling the
tunnel from transmitting data to the intended end. To prevent NAT sessions from being aged, configure
the NAT keepalive function on the IKE gateway behind the NAT device to send NAT keepalive packets
to its peer periodically to keep the NAT session alive.
To configure the IKE NAT keepalive function:
Step
1. Enter system view.
2. Set the IKE NAT keepalive
interval.

Configuring IKE DPD

DPD detects dead peers. It can operate in periodic mode or on-demand mode.
Periodic DPD—Sends a DPD message at regular intervals. It features an earlier detection of dead
•
peers, but consumes more bandwidth and CPU.
• On-demand DPD—Sends a DPD message based on traffic. When the device has traffic to send and
is not aware of the liveness of the peer, it sends a DPD message to query the status of the peer. If the
device has no traffic to send, it never sends DPD messages. This mode is recommended.
The IKE DPD works as follows:
1. The local device sends a DPD message to the peer, and waits for a response from the peer.
2. If the peer does not respond within the retry interval specified by the retry seconds parameter, the
local device resends the message.
3. If still no response is received within the retry interval, the local send the DPD message again. The
system allows a maximum of two retries.
Command
system-view
ike keepalive interval seconds
ike keepalive timeout seconds
Command
system-view
ike nat-keepalive seconds
230
Remarks
N/A
By default, no keepalives are sent
to the peer.
By default, IKE SA keepalive never
times out.
Remarks
N/A
The default interval is 20 seconds.