From: nusid...@redhat.com Date: Tue, 26 Mar 2019 06:13:46 +0530 > From: Numan Siddique <nusid...@redhat.com> > > This patch adds a new action - 'check_pkt_len' which checks the > packet length and executes a set of actions if the packet > length is greater than the specified length or executes > another set of actions if the packet length is lesser or equal to. > > This action takes below nlattrs > * OVS_CHECK_PKT_LEN_ATTR_PKT_LEN - 'pkt_len' to check for > > * OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER - Nested actions > to apply if the packet length is greater than the specified 'pkt_len' > > * OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL - Nested > actions to apply if the packet length is lesser or equal to the > specified 'pkt_len'. > > The main use case for adding this action is to solve the packet > drops because of MTU mismatch in OVN virtual networking solution. > When a VM (which belongs to a logical switch of OVN) sends a packet > destined to go via the gateway router and if the nic which provides > external connectivity, has a lesser MTU, OVS drops the packet > if the packet length is greater than this MTU. > > With the help of this action, OVN will check the packet length > and if it is greater than the MTU size, it will generate an > ICMP packet (type 3, code 4) and includes the next hop mtu in it > so that the sender can fragment the packets. > > Reported-at: > https://mail.openvswitch.org/pipermail/ovs-discuss/2018-July/047039.html > Suggested-by: Ben Pfaff <b...@ovn.org> > Signed-off-by: Numan Siddique <nusid...@redhat.com>
Applied, thanks.
