On 08/10/2024 10:58, Jiri Pirko wrote:
Tue, Oct 08, 2024 at 10:01:40AM CEST, antonio@xxxxxxxxxxx wrote:
Hi,
On 07/10/24 17:32, Jiri Pirko wrote:
Wed, Oct 02, 2024 at 11:02:17AM CEST, antonio@xxxxxxxxxxx wrote:
[...]
+operations:
+ list:
+ -
+ name: dev-new
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Create a new interface of type ovpn
+ do:
+ request:
+ attributes:
+ - ifname
+ - mode
+ reply:
+ attributes:
+ - ifname
+ - ifindex
+ -
+ name: dev-del
Why you expose new and del here in ovn specific generic netlink iface?
Why can't you use the exising RTNL api which is used for creation and
destruction of other types of devices?
That was my original approach in v1, but it was argued that an ovpn interface
needs a userspace program to be configured and used in a meaningful way,
therefore it was decided to concentrate all iface mgmt APIs along with the
others in the netlink family and to not expose any RTNL ops.
Can you please point me to the message id?
<CAHNKnsQnHAdxC-XhC9RP-cFp0d-E4YGb+7ie3WymXVL9N-QS6A@xxxxxxxxxxxxxx>
from Sergey and subsequent replies.
RTNL vs NL topic starts right after the definition of 'ovpn_link_ops'
Recently Kuniyuki commented on this topic as well in:
<20240919055259.17622-1-kuniyu@xxxxxxxxxx>
and that is why I added a default dellink implemetation.
However, recently we decided to add a dellink implementation for better
integration with network namespaces and to allow the user to wipe a dangling
interface.
Hmm, one more argument to have symmetric add/del impletentation in RTNL
In the future we are planning to also add the possibility to create a
"persistent interface", that is an interface created before launching any
userspace program and that survives when the latter is stopped.
I can guess this functionality may be better suited for RTNL, but I am not
sure yet.
That would be quite confusing to have RTNL and genetlink iface to
add/del device. From what you described above, makes more sent to have
it just in RTNL
All in all I tend to agree.
@Jiri: do you have any particular opinion why we should use RTNL ops and not
netlink for creating/destroying interfaces? I feel this is mostly a matter of
taste, but maybe there are technical reasons we should consider.
Well. technically, you can probabaly do both. But it is quite common
that you can add/delete these kind of devices over RTNL. Lots of
examples. People are used to it, aligns with existing flows.
The only counterargument I see is the one brought by Sergey: "the ovpn
interface is not usable after creation, if no openvpn process is running".
However, allowing to create "persistent interfaces" will define a
use-case for having an ovpn device without any userspace process.
@Sergey what is your opinion here? I am not sure persistent interfaces
were discussed at the time you brought your point about RTNL vs NL.
Regards,
Thanks a lot for your contribution.
Regards,
ip link add [link DEV | parentdev NAME] [ name ] NAME
[ txqueuelen PACKETS ]
[ address LLADDR ]
[ broadcast LLADDR ]
[ mtu MTU ] [index IDX ]
[ numtxqueues QUEUE_COUNT ]
[ numrxqueues QUEUE_COUNT ]
[ netns { PID | NETNSNAME | NETNSFILE } ]
type TYPE [ ARGS ]
ip link delete { DEVICE | dev DEVICE | group DEVGROUP } type TYPE [ ARGS ]
Lots of examples of existing types creation is for example here:
https://developers.redhat.com/blog/2018/10/22/introduction-to-linux-interfaces-for-virtual-networking
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Delete existing interface of type ovpn
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
[...]
--
Antonio Quartulli
OpenVPN Inc.
--
Antonio Quartulli
OpenVPN Inc.
