confirmed that sshd 7.7p1 with "IPQoS af21 cs1" also closed connection. On Tue, Aug 28, 2018 at 6:19 PM Stuart Henderson <stu@xxxxxxxxxxxxxxx> wrote: > On 2018/08/28 14:17, Damien Miller wrote: > > On Mon, 27 Aug 2018, Stuart Henderson wrote: > > > > > On 2018-08-27, Zach Cheung <kuroro.zhang@xxxxxxxxx> wrote: > > > > After upgrading my VMware Fusion (10.1.3) Arch Guest to the latest > with > > > > OpenSSH upgraded from 7.7p1 to 7.8p1, found that ssh from macOS > Sierra > > > > (10.12.6) host to Arch guest via local NAT port forwarding failed, > but via > > > > Arch LAN IP worked, downgraded OpenSSH from 7.8p1 to 7.7p1 fixed the > > > > problem. > > > > > > > > Any idea about this bug? > > > > > > I bet it is the QoS change. Try "IPQoS lowdelay,throughput". > > > > Do you have any insight into what is breaking here? I don't believe > > changing the default DSCP values should break connections... > > I think it's probably a NAT bug in VMware Fusion. tcpdump might > give more clues as to how it's broken (maybe it's mangling packets, > maybe it's just rejecting them) but actually fixing it would need > VMware's involvement. > > Short description: OpenSSH 7.8 started marking packets with DSCP > (af21 for interactive, cs1 for bulk) instead of IP TOS ("lowdelay" > for interactive, "throughput" for bulk). VMware Fusion with NAT > port-forwarding to sshd in the guest fails with OpenSSH 7.8. > It should be possible to replicate this failure with older OpenSSH > (6.0 or newer) by using "IPQoS af21 cs1" in sshd_config in the guest. > > Unless any VMware people are reading this, it's probably best if one > of their customers reports it as a bug, I can't imagine it would be > that complicated to fix, the problem will be getting the report past > front-line support and on to the right person. > > _______________________________________________ > openssh-unix-dev mailing list > openssh-unix-dev@xxxxxxxxxxx > https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev > _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev