2018-10-29 21:33:07 |
Steve Langasek |
description |
After upgrade to Ubuntu 18.10, my connection to my employer's VPN server has become unstable.
The server provides both ipv4 and ipv6 endpoints. Since I have global ipv6 at home, my client defaults to connecting over ipv6.
The connection consistently drops after only a few minutes of being connected.
If I force the connection to use ipv4 (by hard-coding the host resolution in /etc/hosts), the connection is stable.
If I use ipv6 and force proto-tcp=yes, the connection is stable.
If I use the default ipv6 and udp, the connection is not stable.
Using tcp for VPNs is suboptimal. Hard-coding addresses in /etc/hosts is suboptimal.
This may be a bug in openvpn rather than in network-manager-openvpn, but I'm starting here.
It's possible there are pathMTU issues involved, but I reproduced this same problem when I was on a different network from my home network (though I did not confirm, when I had access to this other network, that it was ipv6-enabled).
I will work on getting more details about both sides of the network to try to debug this. |
After upgrade to Ubuntu 18.10, my connection to my employer's VPN server has become unstable.
The server provides both ipv4 and ipv6 endpoints. Since I have global ipv6 at home, my client defaults to connecting over ipv6.
The connection consistently drops after only a few minutes of being connected.
If I force the connection to use ipv4 (by hard-coding the host resolution in /etc/hosts), the connection is stable.
If I use ipv6 and force proto-tcp=yes, the connection is stable.
If I use the default ipv6 and udp, the connection is not stable.
Using tcp for VPNs is suboptimal. Hard-coding addresses in /etc/hosts is suboptimal.
This may be a bug in openvpn rather than in network-manager-openvpn, but I'm starting here.
It's possible there are pathMTU issues involved, but I reproduced this same problem when I was on a different network from my home network (though I did not confirm, when I had access to this other network, that it was ipv6-enabled).
I will work on getting more details about both sides of the network to try to debug this.
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ProblemType: Bug
ApportVersion: 2.20.10-0ubuntu13
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
DistroRelease: Ubuntu 18.10
InstallationDate: Installed on 2010-09-24 (2957 days ago)
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release amd64 (20100816.1)
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
Package: network-manager-openvpn 1.8.6-1ubuntu1
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Tags: cosmic
Uname: Linux 4.18.0-10-generic x86_64
UpgradeStatus: Upgraded to cosmic on 2018-10-18 (11 days ago)
UserGroups: adm admin cdrom dialout docker libvirt libvirtd lpadmin lxd mythtv plugdev sambashare sbuild src sudo
_MarkForUpload: True |
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