Overview¶
Fast Path Forwarding IPv4 provides IPv4 forwarding in the fast path.
Features¶
IP forwarding
IP fragmentation
ECMP (Equal Multipath) with priority per route type
VRF support
IPv4 reverse path forwarding check
TCPmss clamping per interface
Next hop marking (if fast path filter module is present)
Routes to same destination with different metrics
Dependencies¶
6WINDGate modules¶
Linux¶
Synchronization of interface flag status
forwardingis a kernel patch (upstream 3.8).Without this patch, the fast path starts with forwarding enabled.
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=edc9e748934c
RPF: Synchronization of interface flag
rp_filteris a kernel patch (upstream 3.8).Without this patch, RPF must be configured manually via
fp-cli.http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=cc535dfb6a85
Optimization of synchronization of ARP entries is a kernel patch (upstream 3.13).
Without this patch, the ARP entries stand in state STALE and the fast path continuously sends hitflags for them.