This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed- artful' to 'verification-done-artful'. If the problem still exists, change the tag 'verification-needed-artful' to 'verification-failed- artful'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-artful -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1743746 Title: 4.13: unable to increase MTU configuration for GRE devices Status in linux package in Ubuntu: Fix Committed Status in linux source package in Artful: Fix Committed Status in linux source package in Bionic: Fix Committed Bug description: [Impact] GRE overlay networks can't carry traffic with MTU > 1500 [Test Case] sudo add-apt-repository cloud-archive:pike sudo apt update sudo apt install openvswitch-switch sudo ovs-vsctl add-br br-tun sudo ovs-vsctl add-port br-tun gre0 -- set interface gre0 type=gre options:remote_ip=10.100.1.1 gre_sys device will be configured with MTU 1472. sudo ip link set gre_sys mtu 65000 will fail with EINVAL. [Regression Potential] [Bug Report] Under Linux 4.13 its not possible to configure GRE tunnel devices with a MTU larger than 1500; this impacts on Open vSwitch (which creates tunnel devices for GRE overlay networking) and the ip tools. The kernel will error with: gre_sys: Invalid MTU 65000 requested, hw max 1500 The side effect of this is that if overlay networks are configured with high MTUs, the gre devices fragment the packets and networking is generally slow/broken. This is resolved as part of the upcoming 4.15 kernel under: https://github.com/torvalds/linux/commit/cfddd4c33c254954927942599d299b3865743146 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743746/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp