Public bug reported:
Existing functionality of l2pop:
L2pop driver on server side -
1) when port binding or status or ip_address(or mac) is updated, notify this
port's FDB(i.e port's
ip address, mac, hosting agent's tunnel ip) to all agents
2) also checks if it is the first or last port on the hosting agent's network,
if so
a) notifies all agents to create/delete tunnels and flood flows to hosting
agent
b) notifies hosting agent about all the existing network ports on other
agents(so that hosting
agent can create tunnels, flood and unicast flows to these ports).
L2pop on agent side, after receiving notification from l2pop driver,
creates/deletes tunnel endpoints, flood, unicast and ARP ovs flows to other
agent's ports.
New Implementation:
But the same functionality can be achieved without l2pop. Whenever a port is
created/updated/deleted, l2 agents get that port(ip, mac and host_id) through
port_update and port_delete RPC notifications. Agents can get get hostname[1]
and tunnel_ip of other agents through tunnel_update(and agents can locally save
this mapping).
As we are getting port's FDB trough these API, we can build the ovs flows
without l2pop FDB.
L2pop driver uses port context's original_port and new_port, to identify
changes to port's FDB. In the new implementation, agent can save port's
FDB(only required fields), so that new port update can be always compared with
saved FDB, and then identify changes to port's FDB.
We can use port's revision_number to maintain order of port's updates.
When l2 agent adds first port on a network(i.e Provisions a local VLAN for the
network), it can request server with a new RPC call to provide all network
port's FDB on other agents. Then it can create flows to all these existing
ports.
DVR implications:
Currently when DVR router port is bound, it notifies all agents[2]. But server
will set port's host_id to ''[3]. Need to change it to calling host and check
the implications.
HA implications:
Port's host_id will always be set to master host. This allows other agents to
create flows to master host only. Need to update HA to use existing DVR
multiple portbinding approach, to allow other agents to create flows to all HA
agents.
Other TODO:
1) In existing implementation, port status updates(update_port_status) won't
notify agent. Need to enhance it.
Advantages
1) Existing l2pop driver code to identify 'active port count' on agent with
multiple servers can be
buggy[4].
2) L2pop driver identifies first port on a agent and notifies it other port's
FDB through RPC.
If this RPC is not reaching the agent for any reason(example, that rpc
worker dead),
then agents can never establish tunnels and flows to other agents.
3) We can remove additional l2pop mechanism driver on the server. Also can
avoid separate l2pop
RPC consumer threads on agent and related concurrency issues[5].
[1] need to patch type_tunnel.py to send hostname as argument for tunnel_update.
[2]
https://github.com/openstack/neutron/blob/master/neutron/plugins/ml2/plugin.py#L1564
[3]
https://github.com/openstack/neutron/blob/master/neutron/plugins/ml2/plugin.py#L542
[4] Got stabilized with https://review.openstack.org/#/c/300539/
[5] https://bugs.launchpad.net/neutron/+bug/1611308
** Affects: neutron
Importance: Undecided
Status: New
** Tags: l2-pop linuxbridge ovs
** Tags added: l2-pop linuxbridge ovs
--
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to neutron.
https://bugs.launchpad.net/bugs/1630981
Title:
Implement l2pop driver functionality in l2 agent
Status in neutron:
New
Bug description:
Existing functionality of l2pop:
L2pop driver on server side -
1) when port binding or status or ip_address(or mac) is updated, notify this
port's FDB(i.e port's
ip address, mac, hosting agent's tunnel ip) to all agents
2) also checks if it is the first or last port on the hosting agent's
network, if so
a) notifies all agents to create/delete tunnels and flood flows to hosting
agent
b) notifies hosting agent about all the existing network ports on other
agents(so that hosting
agent can create tunnels, flood and unicast flows to these ports).
L2pop on agent side, after receiving notification from l2pop driver,
creates/deletes tunnel endpoints, flood, unicast and ARP ovs flows to other
agent's ports.
New Implementation:
But the same functionality can be achieved without l2pop. Whenever a port is
created/updated/deleted, l2 agents get that port(ip, mac and host_id) through
port_update and port_delete RPC notifications. Agents can get get hostname[1]
and tunnel_ip of other agents through tunnel_update(and agents can locally save
this mapping).
As we are getting port's FDB trough these API, we can build the ovs flows
without l2pop FDB.
L2pop driver uses port context's original_port and new_port, to identify
changes to port's FDB. In the new implementation, agent can save port's
FDB(only required fields), so that new port update can be always compared with
saved FDB, and then identify changes to port's FDB.
We can use port's revision_number to maintain order of port's updates.
When l2 agent adds first port on a network(i.e Provisions a local VLAN for
the network), it can request server with a new RPC call to provide all network
port's FDB on other agents. Then it can create flows to all these existing
ports.
DVR implications:
Currently when DVR router port is bound, it notifies all agents[2]. But
server will set port's host_id to ''[3]. Need to change it to calling host and
check the implications.
HA implications:
Port's host_id will always be set to master host. This allows other agents to
create flows to master host only. Need to update HA to use existing DVR
multiple portbinding approach, to allow other agents to create flows to all HA
agents.
Other TODO:
1) In existing implementation, port status updates(update_port_status) won't
notify agent. Need to enhance it.
Advantages
1) Existing l2pop driver code to identify 'active port count' on agent with
multiple servers can be
buggy[4].
2) L2pop driver identifies first port on a agent and notifies it other port's
FDB through RPC.
If this RPC is not reaching the agent for any reason(example, that rpc
worker dead),
then agents can never establish tunnels and flows to other agents.
3) We can remove additional l2pop mechanism driver on the server. Also can
avoid separate l2pop
RPC consumer threads on agent and related concurrency issues[5].
[1] need to patch type_tunnel.py to send hostname as argument for
tunnel_update.
[2]
https://github.com/openstack/neutron/blob/master/neutron/plugins/ml2/plugin.py#L1564
[3]
https://github.com/openstack/neutron/blob/master/neutron/plugins/ml2/plugin.py#L542
[4] Got stabilized with https://review.openstack.org/#/c/300539/
[5] https://bugs.launchpad.net/neutron/+bug/1611308
To manage notifications about this bug go to:
https://bugs.launchpad.net/neutron/+bug/1630981/+subscriptions
--
Mailing list: https://launchpad.net/~yahoo-eng-team
Post to : [email protected]
Unsubscribe : https://launchpad.net/~yahoo-eng-team
More help : https://help.launchpad.net/ListHelp
