I apologize if the 'ASCII Draw' does not appear correctly in your email client. Outlook seems to be changing it..
Hello All,
I wonder if you could help me understand the OVN architecture and specifically, how we might implement this in OpenStack or any other CMS..
The XML document has the following ASCII-Draw picture:
The implication in the dotted box below the CMS is that the CMS Plugin, OVN NorthBound DB, and the ovn-nbd are all part of the same group or module. In other words, for OpenStack, this suggests the solution would contain an OpenStack specific Plugin (of course), OVN Northbound DB and ovn-ndb (perhaps an agent??).
CMS
|
|
+-----------|-----------+
| | |
| OVN/CMS Plugin |
| | |
| | |
| OVN Northbound DB |
| | |
| | |
| ovn-nbd |
| | |
+-----------|-----------+
|
|
+------+
|OVN DB|
+------+
|
|
+------------------+------------------+
| | |
HV 1 | | HV n |
+---------------|---------------+ . +---------------|---------------+
| | | . | | |
| ovn-controller | . | ovn-controller |
| | | | . | | | |
| | | | | | | |
| ovs-vswitchd ovsdb-server | | ovs-vswitchd ovsdb-server |
| | | |
+-------------------------------+ +-------------------------------+
However, the OVN Northbound DB is not the CMS DB ( Neutron DB in the case of OpenStack), it is a Schema defined by OVN. This suggests that the OVN Northbound DB and ovn-nbd is CMS independent and should be outside the CMS implementation.
The OVN Northbound DB and the Central OVN DB could be in the same 'System' (or cluster or systems).
CMS
|
|
+-----------|-----------+
| | |
| OVN/CMS Plugin |
+-----------|-----------+
|
|
|
+-----------|-----------+
| | |
| | |
| OVN Northbound DB |
| | |
| | |
| ovn-nbd |
| | |
+-----------|-----------+
: | :
: | :
+------+
|OVN DB|
+------+
|
|
+------------------+------------------+
| | |
HV 1 | | HV n |
+---------------|---------------+ . +---------------|---------------+
| | | . | | |
| ovn-controller | . | ovn-controller |
| | | | . | | | |
| | | | | | | |
| ovs-vswitchd ovsdb-server | | ovs-vswitchd ovsdb-server |
| | | |
+-------------------------------+ +-------------------------------+
Above is the split that I am talking about. The OVN DB could still be separate as it will likely have different HA requirements than the OVN Northbound (assuming the OVN Northbound could be recreated from the CMS DB).
The above starts to look a bit more like a 'Controller' architecture where something like ODL or another SDN Controller could host the OVN Northbound DB and the ovn-nbd. This also means that assuming the interface between the CMS (and its plugin architecture) is OVSDB protocol to the OVN Northbound DB, only the CMS and its plugin would need to be CMS Specific.
Thoughts...
-Scott Millward
CMS
|
|
+-----------|-----------+
| | |
| OVN/CMS Plugin |
| | |
| | |
| OVN Northbound DB |
| | |
| | |
| ovn-nbd |
| | |
+-----------|-----------+
|
|
+------+
|OVN DB|
+------+
|
|
+------------------+------------------+
| | |
HV 1 | | HV n |
+---------------|---------------+ . +---------------|---------------+
| | | . | | |
| ovn-controller | . | ovn-controller |
| | | | . | | | |
| | | | | | | |
| ovs-vswitchd ovsdb-server | | ovs-vswitchd ovsdb-server |
| | | |
+-------------------------------+ +-------------------------------+
CMS
|
|
+-----------|-----------+
| | |
| OVN/CMS Plugin |
| | |
| | |
| OVN Northbound DB |
| | |
| | |
| ovn-nbd |
| | |
+-----------|-----------+
|
|
+------+
|OVN DB|
+------+
|
|
+------------------+------------------+
| | |
HV 1 | | HV n |
+---------------|---------------+ . +---------------|---------------+
| | | . | | |
| ovn-controller | . | ovn-controller |
| | | | . | | | |
| | | | | | | |
| ovs-vswitchd ovsdb-server | | ovs-vswitchd ovsdb-server |
| | | |
+-------------------------------+ +-------------------------------+