diff options
Diffstat (limited to 'share/man/man4/syncache.4')
| -rw-r--r-- | share/man/man4/syncache.4 | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/share/man/man4/syncache.4 b/share/man/man4/syncache.4 index e92502fd15ff..f83e9b083e45 100644 --- a/share/man/man4/syncache.4 +++ b/share/man/man4/syncache.4 @@ -10,7 +10,7 @@ .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" -.Dd April 12, 2021 +.Dd August 30, 2025 .Dt SYNCACHE 4 .Os .Sh NAME @@ -39,6 +39,8 @@ MIBs for controlling TCP SYN caching .Nm sysctl Cm net.inet.tcp.syncache.count .It .Nm sysctl Cm net.inet.tcp.syncache.see_other +.It +.Nm sysctl Cm net.inet.tcp.syncache.rst_on_sock_fail .El .Sh DESCRIPTION The @@ -107,6 +109,18 @@ and run only with set .Va net.inet.tcp.syncookies_only to 1. +To use +.Nm syncookies +to handle bucket overflows in the +.Nm syncache +set +.Va net.inet.tcp.syncookies +to 1. +The default value for +.Va net.inet.tcp.syncookies_only +is 0 and the default value for +.Va net.inet.tcp.syncookies +is 1. .Pp The .Nm @@ -169,6 +183,9 @@ However, extra .Xr ucred 9 referencing is required on every incoming SYN packet processed. The default is off. +.It Va rst_on_sock_fail +Send a TCP RST segment if the socket allocation fails. +The default is on. .El .Pp Statistics on the performance of the @@ -206,8 +223,16 @@ Entries dropped due to ICMP unreachable messages. Failures to allocate new .Nm entry. +.It Li "cookies sent" +SYN cookies sent in SYN ACK segments. .It Li "cookies received" -Connections created from segment containing ACK. +ACK segments with valid syncookies which resulted in TCP connection +establishment. +.It Li "spurious cookies rejected" +Received ACKs, for which the syncache lookup failed and also no syncookie was +recently sent. +.It Li "failed cookies rejected" +Received ACKs for which the syncookie validation failed. .El .Sh SEE ALSO .Xr netstat 1 , |