On Mon, Sep 3, 2018 at 8:01 PM Fabrice Bacchella <fabrice.bacchella@orange.fr> wrote:

Le 3 sept. 2018 à 18:31, Nir Soffer <nsoffer@redhat.com> a écrit :

On Mon, Sep 3, 2018 at 5:07 PM Fabrice Bacchella <fabrice.bacchella@orange.fr> wrote:
In the release notes, I see:

• BZ 1622700 [downstream clone - 4.2.6] [RFE][Dalton] - Blacklist all local disk in multipath on RHEL / RHEV Host (RHEL 7.5)
Feature:
Blacklist local devices in multipath.

Reason:
multipath repeatedly logs irrelevant errors for local devices.

Result:
Local devices are blacklisted, and no irrelevant errors are logged anymore.

What defines a local disk ? I'm using a SAN on SAS. For many peoples, SAS is only for local disks, but that's not the case. Will other 4.2.6 will detect that ?

We don't have any support for SAS.

If you SAS drives are attached to the host using FC or iSCSI, you are fine.

Nope, they are attached using SAS.

I guess oVirt see them as FCP devices?

Are these disks connected to multiple hosts?

Please share the output of:

    vdsm-client Host getDeviceList
 ...
Where do I find the protocol multipath thinks the drives are using ?

multipath.conf(5) says:

       The protocol strings that multipath recognizes are scsi:fcp, scsi:spi, scsi:ssa, scsi:sbp,
       scsi:srp, scsi:iscsi, scsi:sas, scsi:adt, scsi:ata, scsi:unspec, ccw, cciss, nvme,  and
       undef.  The protocol that a path is using can be viewed by running multipathd show
       paths format "%d %P"

So this should work:

blacklist_exceptions {
        protocol "(scsi:fcp|scsi:iscsi|scsi:sas)"                                                                                                                                                      
}

The best way to make this change is to create a dropin conf file, 
and not touch /etc/multipath.conf, so vdsm will be able to update later.

$cat /etc/multipath/conf.d/local.conf
blacklist_exceptions {
        protocol "(scsi:fcp|scsi:iscsi|scsi:sas)"                                                                                                                                                      
}

I hope it works for overriding vdsm configuration, if not, you will need to 
change /etc/multipath.conf, and mark it as VDSM_PRIVATE like this;

$ head -3 /etc/multipath.conf
# # VDSM REVISION 1.6
# VDSM PRIVATE


Once it works, I suggest to file a bug to support sas disks by default.

Nir