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authorMarkus Bukowski <me@mrbuk.de>2022-01-15 12:35:55 +0100
committerMarkus Bukowski <me@mrbuk.de>2022-01-15 12:51:30 +0100
commitda72f4c39f015644515e0b598aea6f7e5a2a03a7 (patch)
tree0a01d60a435b1cad7a6105228a94744e31a3e9be /docs/configuration/interfaces/pppoe.rst
parentd2a6dae8ca26417a53943e196a7eca2ca175e4b1 (diff)
downloadvyos-documentation-da72f4c39f015644515e0b598aea6f7e5a2a03a7.tar.gz
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Removed MSS from interface, added IP to pppoe
Diffstat (limited to 'docs/configuration/interfaces/pppoe.rst')
-rw-r--r--docs/configuration/interfaces/pppoe.rst70
1 files changed, 70 insertions, 0 deletions
diff --git a/docs/configuration/interfaces/pppoe.rst b/docs/configuration/interfaces/pppoe.rst
index 41f22ed6..ae6a8cba 100644
--- a/docs/configuration/interfaces/pppoe.rst
+++ b/docs/configuration/interfaces/pppoe.rst
@@ -177,6 +177,41 @@ PPPoE options
PPPoE connection must be established over a physical interface. Interfaces
can be regular Ethernet interfaces, VIFs or bonding interfaces/VIFs.
+.. cfgcmd:: set interfaces pppoe <interface> ip adjust-mss <mss>
+
+ As Internet wide PMTU discovery rarely works, we sometimes need to clamp our
+ TCP MSS value to a specific value. This is a field in the TCP options part of
+ a SYN packet. By setting the MSS value, you are telling the remote side
+ unequivocally 'do not try to send me packets bigger than this value'.
+
+ .. note:: This command was introduced in VyOS 1.4 - it was previously called:
+ ``set firewall options interface <name> adjust-mss <value>``
+
+ .. hint:: MSS value = MTU - 20 (IP header) - 20 (TCP header), resulting in
+ 1452 bytes on a 1492 byte MTU.
+
+.. cfgcmd:: set interfaces pppoe <interface> ip disable-forwarding
+
+ Configure interface-specific Host/Router behaviour. If set, the interface will
+ switch to host mode and IPv6 forwarding will be disabled on this interface.
+
+.. cfgcmd:: set interfaces pppoe <interface> ip source-validation <strict | loose | disable>
+
+ Enable policy for source validation by reversed path, as specified in
+ :rfc:`3704`. Current recommended practice in :rfc:`3704` is to enable strict
+ mode to prevent IP spoofing from DDos attacks. If using asymmetric routing
+ or other complicated routing, then loose mode is recommended.
+
+ - strict: Each incoming packet is tested against the FIB and if the interface
+ is not the best reverse path the packet check will fail. By default failed
+ packets are discarded.
+
+ - loose: Each incoming packet's source address is also tested against the FIB
+ and if the source address is not reachable via any interface the packet
+ check will fail.
+
+ - disable: No source validation
+
IPv6
----
@@ -189,6 +224,41 @@ IPv6
:var0: pppoe
:var1: pppoe0
+.. cfgcmd:: set interfaces pppoe <interface> ipv6 adjust-mss <mss>
+
+ As Internet wide PMTU discovery rarely works, we sometimes need to clamp our
+ TCP MSS value to a specific value. This is a field in the TCP options part of
+ a SYN packet. By setting the MSS value, you are telling the remote side
+ unequivocally 'do not try to send me packets bigger than this value'.
+
+ .. note:: This command was introduced in VyOS 1.4 - it was previously called:
+ ``set firewall options interface <name> adjust-mss <value>``
+
+ .. hint:: MSS value = MTU - 20 (IP header) - 20 (TCP header), resulting in
+ 1452 bytes on a 1492 byte MTU.
+
+.. cfgcmd:: set interfaces pppoe <interface> ipv6 disable-forwarding
+
+ Configure interface-specific Host/Router behaviour. If set, the interface will
+ switch to host mode and IPv6 forwarding will be disabled on this interface.
+
+.. cfgcmd:: set interfaces pppoe <interface> ipv6 source-validation <strict | loose | disable>
+
+ Enable policy for source validation by reversed path, as specified in
+ :rfc:`3704`. Current recommended practice in :rfc:`3704` is to enable strict
+ mode to prevent IP spoofing from DDos attacks. If using asymmetric routing
+ or other complicated routing, then loose mode is recommended.
+
+ - strict: Each incoming packet is tested against the FIB and if the interface
+ is not the best reverse path the packet check will fail. By default failed
+ packets are discarded.
+
+ - loose: Each incoming packet's source address is also tested against the FIB
+ and if the source address is not reachable via any interface the packet
+ check will fail.
+
+ - disable: No source validation
+
*********
Operation
*********