If you're only looking for tcp checkpoint-restore (and not while process) using network namespaces worked, even before the advent of CAP_CHECKPOINT_RESTORE in t

If you're only looking for tcp checkpoint-restore (and not while process) using network namespaces worked, even before the advent of CAP_CHECKPOINT_RESTORE in the Linux kernel (I wish they'd kept checkpoint separate but it's a fight for another day). Works for me on recent kernels. The problem with this the criu/kernel approach is that you need to go through some lengths to pause the low-layer packet stream.