On Tue, Jun 04, 2019 at 09:31:42PM -0700, Cong Wang wrote: >> This works fine for large packets, but the system in the other end >> drops smaller packets, such as ARP requests and small ICMP pings. > Is the other end Linux too?
Yes and no. The other end is Linux with Open vSwitch, which sends the packet on to a VM. The VM is an appliance which I do not control, and while the management plane runs Linux, the data plane is as far as I know implemented in userspace. The appliance itself can also run EoGRE directly, but I haven't gotten it to work. > If the packet doesn't go through any real wire, it could still be accepted > by Linux even when it is smaller than ETH_ZLEN, I think. Yes, but that's just Linux accepting something invalid, no? It doesn't mean it should be sending it out. > Some hardware switches pad for ETH_ZLEN when it goes through a real wire. All hardware switches should; it's a 802.1Q demand. (Some have traditionally been buggy in that they haven't added extra padding back when they strip the VLAN tag.) > It is still too early to say it is a bug. Is this a regression? I haven't tried it with earlier versions; I would suspect it's not a regression. /* Steinar */ -- Homepage: https://www.sesse.net/
