diff options
Diffstat (limited to 'share/man/man4/tcp.4')
| -rw-r--r-- | share/man/man4/tcp.4 | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/share/man/man4/tcp.4 b/share/man/man4/tcp.4 index a95078f..7814a0d 100644 --- a/share/man/man4/tcp.4 +++ b/share/man/man4/tcp.4 @@ -34,7 +34,7 @@ .\" From: @(#)tcp.4 8.1 (Berkeley) 6/5/93 .\" $FreeBSD$ .\" -.Dd November 8, 2013 +.Dd October 13, 2014 .Dt TCP 4 .Os .Sh NAME @@ -516,8 +516,30 @@ ECN allows a TCP sender to reduce the transmission rate in order to avoid packet drops. .It Va ecn.maxretries Number of retries (SYN or SYN/ACK retransmits) before disabling ECN on a -specific connection. This is needed to help with connection establishment +specific connection. +This is needed to help with connection establishment when a broken firewall is in the network path. +.It Va pmtud_blackhole_detection +Turn on automatic path MTU blackhole detection. +In case of retransmits we will +lower the MSS to check if it's MTU problem. +If current MSS is greater than +configured value to try, it will be set to it, otherwise, MSS will be set to +default values +.Po Va net.inet.tcp.mssdflt +and +.Va net.inet.tcp.v6mssdflt +.Pc . +.It Va pmtud_blackhole_mss +MSS to try for IPv4 if PMTU blackhole detection is turned on. +.It Va v6pmtud_blackhole_mss +MSS to try for IPv6 if PMTU blackhole detection is turned on. +.It Va pmtud_blackhole_activated +Number of times the code was activated to attempt a MSS downshift. +.It Va pmtud_blackhole_min_activated +Number of times the blackhole MSS was used in an attempt to downshift. +.It Va pmtud_blackhole_failed +Number of times that we failed to connect after we downshifted the MSS. .El .Sh ERRORS A socket operation may fail with one of the following errors returned: |
