Hello Zhu Yanjun, On Thursday, July 16, 2020 05:41 CEST, Zhu Yanjun <zyjzyj2...@gmail.com> wrote:
> > Please check this > https://developers.redhat.com/blog/2019/05/17/an-introduction-to-linux-virtual-interfaces-tunnels/#gre > > Perhaps gretap only forwards ip (with L2 header) packets. That does not seem to be the case. E.g. root@fo-exit:/home/user# tcpdump -i intra16 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on intra16, link-type EN10MB (Ethernet), capture size 262144 bytes 09:05:12.619206 IP 10.88.16.100 > 10.88.16.200: GREv0, length 46: ARP, Request who-has 10.42.42.200 tell 10.42.42.100, length 28 09:05:12.619278 IP 10.88.16.200 > 10.88.16.100: GREv0, length 46: ARP, Reply 10.42.42.200 is-at da:9d:34:64:cb:8d (oui Unknown), length 28 09:05:14.054026 IP 10.88.16.200 > 10.88.16.100: GREv0, length 46: ARP, Request who-has 10.42.42.100 tell 10.42.42.200, length 28 09:05:14.107143 IP 10.88.16.100 > 10.88.16.200: GREv0, length 46: ARP, Reply 10.42.42.100 is-at d6:49:e5:19:52:16 (oui Unknown), length 28 ^C > > Possibly "arp -s" could help to workaround this. Riccardo P. Bestetti
