neutron/doc/source/contributor/internals/ovn
Daniel Alvarez Sanchez 36ba1cc319 [ovn][metadata] Remove metadata readiness mechanism
Prior to this patch, the metadata agent was writing into SB
database when a network had been provisioned with metadata
on a particular chassis.

Then, neutron-server would wait for that event to happen with
a 15s timeout before sending the vif-plugged event to Nova.

By removing this mechanism:

1) We'll save writes to OVN SB database which, in highly loaded
systems and at scale reduces significantly the load on ovsdb-server.

2) Ignoring healthchecks (that still requires write to the SB DB),
we can make OVN metadata agent to connect to slave instances when
using active-backup OVN databases since writes are not needed.

3) There's a chance that the VM boots very fast and requests
metadata before the service is ready but since the timeout was
15 seconds, we can safely rely on the the cloud-init retries.

Signed-off-by: Daniel Alvarez Sanchez <dalvarez@redhat.com>
Change-Id: Ia6cd7a9a3b9662a9a8ce106e01a93c357c255956
2021-06-03 16:09:31 +00:00
..
data_model.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
database_consistency.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
distributed_ovsdb_events.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
index.rst [OVN] security group logging support (1 of 2) 2021-02-24 10:37:43 -05:00
l3_ha_rescheduling.rst Improve terminology in the Neutron tree 2020-08-19 16:47:53 -04:00
loadbalancer.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
metadata_api.rst [ovn][metadata] Remove metadata readiness mechanism 2021-06-03 16:09:31 +00:00
native_dhcp.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
ovn_network_logging.rst [OVN] security group logging support (1 of 2) 2021-02-24 10:37:43 -05:00
ovn_worker.rst Merge networking-ovn documentation into neutron 2020-02-13 18:54:15 +09:00
port_forwarding.rst [ovn]: port forwarding -- move documentation to better place 2020-09-03 19:07:31 -04:00