HP-UX IPSec version A.02.00 Administrator's Guide

Configuring HP-UX IPSec
Step 3: Configuring IKE Policies
Chapter 3 89
Step 3: Configuring IKE Policies
Complete this step only if you are using dynamic keys for IPSec. You do
not need to configure IKE policies if you are using only manual keys for
IPSec, or if you are only using HP-UX IPSec to discard packets. If you are
not using dynamic keys, go to “Step 6: Configuring the Bypass List (Local
IPv4 Addresses)” on page 101
HP-UX IPSec uses the parameters in an IKE policy when using the IKE
protocol to establish ISAKMP/Main Mode (MM) Security Associations
(SAs) with remote systems. IPSec uses ISAKMP/MM SAs to negotiate
IPSec SAs; an ISAKMP/MM SA must exist with a remote system before
IPSec can negotiate IPSec SAs.
You must have at least one IKE policy if you are using dynamic keys for
IPSec. If HP-UX IPSec cannot find an IKE policy with a remote address
specification that matches the remote system, the ISAKMP/MM SA
negotiation will fail.
HP recommends that you use an ipsec_config batch file to configure
IKE policies.
Policy Order and Selection
When HP-UX IPSec needs to establish an ISAKMP/MM SA, it searches
the IKE policies according to the value of the priority parameter for
each policy and selects the first policy with the IP address and prefix
specifications that match the remote system’s address.
Automatic Priority Increment
You can explicitly set the priority of an IKE policy with the priority
argument, or you can use the automatic priority increment value for IKE
policies in the profile file (the priority parameter value in the
IKEPolicy-Defaults section of the profile file). If you do not specify a
priority argument, ipsec_config assigns a priority value that is set to
the current highest priority value (lowest priority) in the configuration
data base, incremented by the automatic priority increment value for
IKE policies. The result is that the new policy will be the last policy
evaluated before the default policy. The default automatic priority
increment value (priority) is 10.