From: xu xin <xu.xin16@xxxxxxxxxx> The updating way of pmtu has changed, but documentation is still in the old way. See commit-id 28d35bcdd3925e7293408cdb8aa5f2aac5f0d6e3. So This patch fix interpretation of ip_no_pmtu_disc. Besides, min_pmtu seems not to be discoverd, but set. Reported-by: Zeal Robot <zealci@xxxxxxxxxx> Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx> --- Documentation/networking/ip-sysctl.rst | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c04431144f7a..dd5e53318805 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -25,9 +25,11 @@ ip_default_ttl - INTEGER ip_no_pmtu_disc - INTEGER Disable Path MTU Discovery. If enabled in mode 1 and a fragmentation-required ICMP is received, the PMTU to this - destination will be set to min_pmtu (see below). You will need - to raise min_pmtu to the smallest interface MTU on your system - manually if you want to avoid locally generated fragments. + destination will be set to the smallest of the old MTU + and ip_rt_min_pmtu (see __ip_rt_update_pmtu() in + net/ipv4/route.c). You will need to raise min_pmtu to the + smallest interface MTU on your system manually if you want to + avoid locally generated fragments. In mode 2 incoming Path MTU Discovery messages will be discarded. Outgoing frames are handled the same as in mode 1, @@ -49,7 +51,7 @@ ip_no_pmtu_disc - INTEGER Default: FALSE min_pmtu - INTEGER - default 552 - minimum discovered Path MTU + default 552 - minimum set Path MTU ip_forward_use_pmtu - BOOLEAN By default we don't trust protocol path MTUs while forwarding -- 2.25.1
