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Document route caching, how it can be enabled, and its consequences.

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Wording by:	cperciva
This commit is contained in:
Gleb Smirnoff 2004-12-06 19:31:35 +00:00
parent ddc6c40075
commit fc2857ad10
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=138474
1 changed files with 12 additions and 1 deletions
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@ -150,9 +150,20 @@ performs both martian and ingress filtering against the outer source address
on egress.
Note that martian/ingress filters are in no way complete.
You may want to secure your node by using packet filters.
Ingress filtering can be turned off by
Ingress filtering can break tunnel operation in an asymmetrically
routed network.
It can be turned off by
.Dv IFF_LINK2
bit.
.Ss Route caching
Processing each packet requires two route lookups: first on the
packet itself, and second on the tunnel destination.
This second route can be cached, increasing tunnel performance.
However, in a dynamically routed network, the tunnel will stick
to the cached route, ignoring routing table updates.
Route caching can be enabled with the
.Dv IFF_LINK0
flag.
.\"
.Ss Miscellaneous
By default,