[libvirt] [PATCH 4/5] virISCSIScanTargets: Honour iSCSI interface

[John Ferlan]

On 07/03/2018 01:08 AM, Michal Prívozník wrote:
> On 07/03/2018 01:38 AM, John Ferlan wrote:
>>
>>
>> On 06/29/2018 11:01 AM, Michal Privoznik wrote:
>>> When scanning for targets, iSCSI might give different results
>>> depending on the interface used. This is basically just name of
>>
>> assuming this means whether the initiatoriqn interface was used
> 
> Yes.
> 
>>
>>> config file under /etc/iscsi/ifaces to use. The file contains
>>> initiator IQN thus different results claim.
>>>
>>
>> Strange to have activity here - was there a bz? Or something found by
>> the (I assume) GSoC project:
>>
>> https://www.redhat.com/archives/libvir-list/2018-June/msg00249.html
>>
>> Touching something that's been avoided for 8 years is always scary, but
>> if it's broken, then sure it ought to be fixed.
> 
> There is no BZ. And yes, the GSoC project got me experimenting (because
> for libiscsi backend we will have to make IQN required since libiscsi
> does not parse anything from /etc/iscsi nor initiatorname.iscsi). And
> while experimenting I've tired to put my own IQN into iscsi pool we
> already have and found this bug.
> 

FWIW: To a degree this is restoring the initiatoriqn argument that
commit 027986f5 removed...

[...]

>>> +static int
>>> +virISCSIScanTargetsInternal(const char *portal,
>>> +                            const char *ifacename,
>>> +                            size_t *ntargetsret,
>>> +                            char ***targetsret);
>>> +
>>> +
>>>  struct virISCSISessionData {
>>>      char *session;
>>>      const char *devpath;
>>> @@ -286,9 +293,10 @@ virISCSIConnection(const char *portal,
>>>               * iscsiadm doesn't let you send commands to the Interface IQN,
>>>               * unless you've first issued a 'sendtargets' command to the
>>>               * portal. Without the sendtargets all that is received is a
>>> -             * "iscsiadm: No records found"
>>> +             * "iscsiadm: No records found". However, we must ensure that
>>> +             * the command is issued over interface name we invented above.
>>
>> "invented" - again is this the make sure it's issued over the
>> initiatoriqn interface?
> 
> Yes. And we construct the interface name at the beginning of this function.
> 

Oh right, the virStorageBackendCreateIfaceIQN call which creates that
libvirt-iface-* name. That's just one of those context things that you
know when you've been working through the code ;-).

Still without the next patch, does this work?

John