[ovs-discuss] [ovs-dev] Deletion of Indirect Groups on Ovs2.5

[Simon Horman]

On Wed, Mar 16, 2016 at 05:48:23PM +0000, Shuva Jyoti Kar wrote:
> Hello,
> 
> I am trying deletion of an indirect group on ovs2.5 . Now when I try to delete the group using the group-id and group-type without the buckets the group-deletion fails with an error OFPGMFC_INVALID_GROUP
> 
> The Openflow  1.3.5 spec says that "If a delete request includes some buckets in the Group-Mod message, then the switch must return an ofp_error_msg with OFPET_GROUP_MOD_FAILED type and OFPGMFC_INVALID_GROUP code."
> 
> I also find that if I delete the group without the group-type it goes through(have seen the same through cli). Since the Openflow1.3.5 specification states :
> "For delete requests (OFPGC_DELETE), if no group entry with the specified group identifier currently exists in the group table, no error is recorded, and no group table modification occurs. Otherwise, the group is removed, and all flow entries containing this group in a Group action are also removed. The group type need not be specified for the delete request. Delete also differs from an add or modify with no buckets specified in that future attempts to add the group identifier will not result in a group exists error. If one wishes to effectively delete a group yet leave in flow entries using it, that group can be cleared by sending a modify with no buckets specified."
> 
> Sending the group-type should not result in the group-deletion failing as that is not mandatory by the spec.
> 
> Is this a bug in ovs2.5 ?

Hi Shuva,

I see a problem in implementing the above in that the type field
is always present in group modification entries (struct ofp_group_mod)
and thus it doesn't seem to be an obvious way to omit it.

One possibility I see would be to ignore the type when processing group
deletion requests - perhaps this was the intention of the specification, I
am unsure.