TCP repair TODO

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TCP repair feature in the Linux kernel is supposed to help migrating a TCP socket. It's not yet complete and this page lists what is to be done.

Transitional states
Currently we support sockets in closed and establised states. However, if a socket is in e.g. syn-sent state the process of turning it into established can last long. We should teach the kernel and crtools to checkpoint and restore this and other states
Optimized restore
Currently the whole outgoing queue is restored in a "all was sent, waiting for ACK-s" state. After this the data that was really not sent yet will be re-transmitted after a while. This will make the connection work, but will delay it for some time. Need to improve this.
Timestamps
If a TCP socket will get live-migrated from one box to another the timestamps (which are typically ON) will get screwed up -- the new kernel will generate TS values that has nothing to do with what they were on dump. The solution is to yet again fix the kernel and put a "timestamp offset" on a socket.
OOB data
Nothing to say here actually. This data is just not supported currently.