Bug 1610711

Summary:	[OVN] Metadata service won't work on SRIOV deployments with Neutron DHCP agents
Product:	Red Hat OpenStack	Reporter:	Daniel Alvarez Sanchez <dalvarez>
Component:	python-networking-ovn	Assignee:	Daniel Alvarez Sanchez <dalvarez>
Status:	CLOSED NEXTRELEASE	QA Contact:	Eran Kuris <ekuris>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	13.0 (Queens)	CC:	apevec, dalvarez, ekuris, jlibosva, lhh, lmartins, majopela, tfreger
Target Milestone:	zstream	Keywords:	Triaged, ZStream
Target Release:	13.0 (Queens)
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	python-networking-ovn-4.0.3-2.el7ost	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:
Clones:	1613384 1666360 (view as bug list)		Environment:
Last Closed:	2019-10-01 13:56:25 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1673027, 1683568
Bug Blocks:	1666360

Description Daniel Alvarez Sanchez 2018-08-01 09:05:15 UTC

Description of problems:

1)
When using SRIOV in OVN we need to deploy Neutron DHCP agents to capture the DHCP requests from the instances on the controller nodes. If DHCP agents are deployed on HA, it means that 3 DHCP ports will be created.

Currently, networking-ovn expects only 1 DHCP port per network to serve metadata and it won't work as it is right now [0].

We shall reuse one of those DHCP ports for the distributed OVN metadata of non SRIOV instances.


2)
Even after 1) is fixed, SRIOV instances won't be able to reach the local metadata services on compute nodes since the requests will skip the hypervisor. We should enable Neutron Metadata Agent on these deployments as well as the isolated metadata case for the DHCP so that metadata is served through the controller/network nodes.

[0] https://github.com/openstack/networking-ovn/blob/5.0.0.0b3/networking_ovn/common/ovn_client.py#L1510

Comment 1 Daniel Alvarez Sanchez 2018-08-07 13:29:18 UTC

As discussed in the squad meeting, we'll first go with config drive for serving metadata in SRIOV deployments (this way we won't deploy Neutron metadata agent). In the future we can look at how to deploy OVN metadata agent in controllers also for the SRIOV case. A fix is still needed in networking-ovn to handle multiple ports.

Comment 5 Daniel Alvarez Sanchez 2019-01-15 15:56:37 UTC

We merged this patch [0] to support both neutron dhcp agent ports and metadata ports.
I'll do the backport to 13

[0] https://review.openstack.org/#/c/620860/

Comment 8 Eran Kuris 2019-02-27 14:36:13 UTC

Blocked by https://bugzilla.redhat.com/show_bug.cgi?id=1683568

Comment 10 Daniel Alvarez Sanchez 2019-03-22 07:24:00 UTC

(In reply to Eran Kuris from comment #8)
> Blocked by https://bugzilla.redhat.com/show_bug.cgi?id=1683568

Hi Eran, why would this BZ blocked by the support of 'flat' networks ?

Comment 11 Daniel Alvarez Sanchez 2019-03-22 07:25:34 UTC

Oh ok was a confusion as Lucas changed the title of BZ 1683568, it's blocked due to the support of both 'flat' and 'vlan' tenant networks. Now I get it.
Technically we could verify this independently by booting a VM on a provider network, right?

Comment 12 Eran Kuris 2019-03-24 07:50:55 UTC

(In reply to Daniel Alvarez Sanchez from comment #10)
> (In reply to Eran Kuris from comment #8)
> > Blocked by https://bugzilla.redhat.com/show_bug.cgi?id=1683568
> 
> Hi Eran, why would this BZ blocked by the support of 'flat' networks ?

Hi Daniel,

As you mentioned in comment 11 the title was changed. This bug is blocked by the bug: https://bugzilla.redhat.com/show_bug.cgi?id=1673027

Yes, we can deploy OVN -SRIOV setup with a workaround and verify this bug but we don't do that because it's not the right process.

Comment 13 Jakub Libosvar 2019-10-01 13:56:25 UTC

SRIOV is not supported in OSP13, should be supported starting OSP16, see bug 1666684.