Under man7/tcp.7 please mention the "2" value for tcp_syncookies, which is no longer a boolean, default "1". First mentioned in kernel 3.12 https://elixir.bootlin.com/linux/v3.12/source/Documentation/networking/ip-sysctl.txt#L443 The kernel documentation is rather ungrammatical, so suggest instead: > Set to 2 to send syncookies unconditionally, which can be useful for network testing (since Linux 3.12). Thanks, Phil
