Hey,
I wanted to test SRv6. Always between two clients (client 1 <-> client 2).
If I do the encapsulation on the client everything works smooth as expected.
Client 1 (encap SRv6 Tunnel) <- 2001::/64-> Router 1 <- 2002::/64 -> Router 2 <- 2003::/64 -> Client 2
ip -6 route add 2003::/64 dev eth0 encap seg6 mode encap segs 2001::1,2002::2
If I do the encapsulation on the router and use a default route on the client it no longer works so smooth. 
Client 1 <- 2001::/64-> Router 1 (encap SRv6 Tunnel) <- 2002::/64 -> Router 2 <- 2003::/64 -> Client 2
- Ping works
- iperf3 connection works in reverse mode (since we have a flow label)
- iperf3 forward connection does no longer work
ip -6 route add 2003::/64 dev eth0 encap seg6 mode encap seg 2002::2
Any idea, why this is the case?
This is so weird:
[nick@cool ~]$ iperf3 -c 2003::2
Connecting to host 2003::2, port 5201
[ 5] local 2000::2 port 57410 connected to 2003::2 port 5201
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 106 KBytes 867 Kbits/sec 2 1.39 KBytes
[ 5] 1.00-2.00 sec 0.00 Bytes 0.00 bits/sec 1 1.39 KBytes
[ 5] 2.00-3.00 sec 0.00 Bytes 0.00 bits/sec 0 1.39 KBytes
^C[ 5] 3.00-3.46 sec 0.00 Bytes 0.00 bits/sec 1 1.39 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-3.46 sec 106 KBytes 251 Kbits/sec 4 sender
[ 5] 0.00-3.46 sec 0.00 Bytes 0.00 bits/sec receiver
iperf3: interrupt - the client has terminated
