Hi Pablo, libnftnl commit cdaea7f1ced0 ("flowtable: allow to specify size") added the enum value NFTA_FLOWTABLE_SIZE, but this was not first added to the kernel. As such, libnftnl's header and the kernel are out of sync. Since then, NFTA_FLOWTABLE_FLAGS has been added to the kernel. This means NFTA_FLOWTABLE_SIZE in libnftnl and NFTA_FLOWTABLE_FLAGS in the kernel have the same enum value. Luckily NFTA_FLOWTABLE_FLAGS was just recently added to -next, so we should be able to fix this without too much headache. Thanks. Eric.