HP 5500 HI Series, Configuration Manual

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Step Command Remarks
11. Apply a DPD detector to the
IKE peer.
dpd dpd-name
Optional.
No DPD detector is applied to an
IKE peer by default.
For more information about DPD
configuration, see "
Configuring a
DPD detector ."
NOTE:
After modifying the configuration of an IPsec IKE peer, execute the reset ipsec sa and reset ike sa
commands to clear existing IPsec and IKE SAs. Otherwise, SA re-negotiation will fail.
Setting keepalive timers
IKE maintains the link status of an ISAKMP SA by keepalive packets. Generally, if the peer is configured
with the keepalive timeout, you must configure the keepalive packet transmission interval on the local end.
If the peer receives no keepalive packet during the timeout interval, the ISAKMP SA will be tagged with
the TIMEOUT tag (if it does not have the tag), or be deleted along with the IPsec SAs it negotiated (when
it has the tag already).
To set the keepalive timers:
Step Command Remarks
1. Enter system view. system-view N/A
2. Set the ISAKMP SA keepalive
interval.
ike sa keepalive-timer interval
seconds
No keepalive packet is sent by
default.
3. Set the ISAKMP SA keepalive
timeout.
ike sa keepalive-timer timeout
seconds
No keepalive packet is sent by
default.
NOTE:
The keepalive timeout configured at the local end must be longer than the keepalive interval configured at
the remote end. Since it seldom occurs that more than three consecutive packets are lost on a network, the
keepalive timeout can be configured to be three times of the keepalive interval.
Setting the NAT keepalive timer
If IPsec traffic needs to pass through NAT security gateways, you must configure the NAT traversal
function. If no packet travels across an IPsec tunnel in a certain period of time, the NAT mapping may get
aged and be deleted, disabling the tunnel beyond the NAT gateway from transmitting data to the
intended end. To prevent NAT mappings from being aged, an ISAKMP SA behind the NAT security
gateway sends NAT keepalive packets to its peer at a certain interval to keep the NAT session alive.
To set the NAT keepalive timer:
Step Command Remarks
1. Enter system view. system-view N/A