You have been subscribed to a public bug: Ubuntu's kernel is compiled with CONFIG_IPDDP=m, which, because of an upstream bug, means that IP-over-DDP packets (DDP type 22) are silently dropped. This is true even if the generated "ipddp" module is not loaded; so if this module is compiled, there is no way to listen for these packets.
One solution would be to fix the module. Another (what CentOS appears to do?) would be to not compile the "ipddp" module at all -- remove CONFIG_IPDDP from the kernel's config. Copying from the upstream bug for specific details: https://bugzilla.kernel.org/show_bug.cgi?id=115031 """ When a kernel is compiled with "ipddp" as a module, but the module is not loaded, DDP packets of type 22 (IP-over-DDP) are silently dropped. Steps to reproduce: 1. Compile a kernel with 'ipddp' as a module. Do not load the module; make sure it is not loaded, just compiled. 2. Open up a DDP listening socket for packets of type 22, on any supported network interface. (Tested with Ethernet.) 3. Attempt to connect to and send data to this socket Expected behavior: - If module is loaded, packets will be unwrapped by the kernel and emitted as IP packets (so will not be received by the listening DDP socket) - If module is not present, packets will be passed through to the listening DDP socket Actual behavior: - If module is not present but was compiled during the kernel build process, packets are silently discarded by the kernel - If module is not present and was not compiled during the kernel build process, packets are passed through as expected """ ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- IP-over-DDP packets dropped https://bugs.launchpad.net/bugs/1559772 You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. -- 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
