----- Original Message ----- > From: "Niels de Vos" <ndevos@xxxxxxxxxx> > To: "Jon Heese" <jonheese@xxxxxxxxxxxx> > Cc: "Dan Lambright" <dlambrig@xxxxxxxxxx>, "Gluster-users@xxxxxxxxxxx List" <gluster-users@xxxxxxxxxxx>, "Humble > Chirammal" <hchiramm@xxxxxxxxxx>, "Lalatendu Mohanty" <lmohanty@xxxxxxxxxx> > Sent: Friday, April 3, 2015 4:20:05 AM > Subject: Re: iscsi and distributed volume > > On Thu, Apr 02, 2015 at 12:08:00AM +0000, Jon Heese wrote: > > Dan, > > > > I've read your blog post about this, but I've been unable to find a way > > to install this "plugin" on CentOS 6 for use with tgtd. > > > > There appears to be a "scsi-target-utils-gluster" RPM out there that has > > what appears to be a module that would accomplish this, but I can only > > find this package for EL7-based OSes. > > > > Do I have to build the module myself for tgtd on CentOS 6? If so, do > > you have instructions to do so? Thanks. Here is what I do. I have not tried on RHEL/CentOS6. Download the target daemon's source: $ git clone https://github.com/fujita/tgt.git Download the gluster development API: $ sudo yum -y install glusterfs-api-devel Set the GLFS_BS environment variable. $ export GLFS_BD=1 Go into the the directory and compile/install. $ cd tgt; sudo make -j install More instructions are in the doc/README.glfs subdirectory, also here: https://forge.gluster.org/gfapi-module-for-linux-target-driver-/gfapi-module-for-linux-target-driver-/blobs/master/doc/README.glfs I have not done much with it in a year. Its good hearing of interest in gluster+iSCSI. Let us know your suggestions. Dan > > This definitely sounds as if we should get it included in the CentOS > Storage SIG repositories. > > http://wiki.centos.org/SpecialInterestGroup/Storage > > I am not sure yet how packages get added to the SIG, Lala and Humble on > CC should be able to explain/help with that. > > For now, rebuilding your own package seems needed :-/ I would start with > the EL7 version and build that on a EL6 system with glusterfs-api-devel > installed. > > HTH, > Niels > > > > > Regards, > > Jon Heese > > > > On 4/1/2015 4:21 PM, Dan Lambright wrote: > > > incidentally , for all you iSCSI on gluster fans.. gluster has a "plugin" > > > to LIO and the target daemon (tgt). The plugin makes it so the server > > > can send IO directly between the iSCSI server and gluster process in > > > user space (as opposed to routing it all through FUSE). Its a nice speed > > > up, in case anyone is looking for a performance bump :) > > > > > > ----- Original Message ----- > > >> From: "Jon Heese" <jonheese@xxxxxxxxxxxx> > > >> To: "Gluster-users@xxxxxxxxxxx List" <gluster-users@xxxxxxxxxxx> > > >> Sent: Wednesday, April 1, 2015 3:20:41 PM > > >> Subject: Re: iscsi and distributed volume > > >> > > >> Or use multipath I/O (assuming your iSCSI initiator OS supports it) to > > >> mount > > >> the iSCSI LUN on both nodes in an active/passive manner. > > >> > > >> I do this with tgtd directly on the Gluster nodes to serve up iSCSI > > >> disks > > >> from an image file sitting on a replicated volume to a VMware ESXi 5.5 > > >> cluster. > > >> > > >> If you go this route, be sure to configure the iSCSI initiator(s) > > >> multipath > > >> to be active/passive (or similar) as my testing with round-robin > > >> produced > > >> very poor performance and data corruption. > > >> > > >> Regards, > > >> Jon Heese > > >> ________________________________________ > > >> From: gluster-users-bounces@xxxxxxxxxxx > > >> <gluster-users-bounces@xxxxxxxxxxx> > > >> on behalf of Paul Robert Marino <prmarino1@xxxxxxxxx> > > >> Sent: Wednesday, April 01, 2015 2:59 PM > > >> To: Dan Lambright > > >> Cc: Gluster-users@xxxxxxxxxxx List > > >> Subject: Re: iscsi and distributed volume > > >> > > >> You do realize you would have to put the ISCSI target disk image on > > >> the mounted Gluster volume not directly on the brick. > > >> So as long as you have replication your volume would remain accessible. > > >> You can not point the ISCSI process directly to the brick or > > >> replication and striping wont work properly. > > >> That said you could consider using something like keepalived with a > > >> monitoring script to handle a VIP for failover in case a node or some > > >> of the underlying processes go down. > > >> > > >> > > >> On Wed, Apr 1, 2015 at 10:17 AM, Dan Lambright <dlambrig@xxxxxxxxxx> > > >> wrote: > > >>> > > >>> > > >>> ----- Original Message ----- > > >>>> From: "Roman" <romeo.r@xxxxxxxxx> > > >>>> To: gluster-users@xxxxxxxxxxx > > >>>> Sent: Wednesday, April 1, 2015 4:38:50 AM > > >>>> Subject: iscsi and distributed volume > > >>>> > > >>>> Hi devs, list! > > >>>> > > >>>> I've got somewhat simple but in same time pretty difficult question. > > >>>> But > > >>>> I'm > > >>>> running glusterf in production and don't have any option to test > > >>>> myself :( > > >>>> > > >>>> say I've got a distributed gluster volume of 2x350GB > > >>>> I want to export ISCSI target for M$ server and I want it to be 600GB. > > >>>> I understand, that when I create a large file for ISCSI target with > > >>>> dd, it > > >>>> will be distributed between two bricks. And here comes the question: > > >>>> > > >>>> What will happen when > > >>>> > > >>>> 1. one of bricks goes down? Ok, simple - target won't be accessible. > > >>>> 2. would be data available again, when the brick comes back up? (ie > > >>>> failure > > >>>> due to network or power) > > >>>> > > >>>> yes, we have backup server and ups and generator, as we are running > > >>>> DC, > > >>>> but > > >>>> I'm just curious if we will have to restore the data from backups or > > >>>> it > > >>>> will > > >>>> be available after brick comes back up? > > >>> > > >>> What kind of gluster volume is it- I would hope it is replicated? > > >>> > > >>> Data within the file is not distributed between two bricks, unless your > > >>> volume type is striped. > > >>> > > >>> Assuming its replicated, if one brick went down, the other replica > > >>> would > > >>> continue to operate, so you would have availability. > > >>> > > >>> > > >>>> > > >>>> > > >>>> > > >>>> -- > > >>>> Best regards, > > >>>> Roman. > > >>>> > > >>>> _______________________________________________ > > >>>> Gluster-users mailing list > > >>>> Gluster-users@xxxxxxxxxxx > > >>>> http://www.gluster.org/mailman/listinfo/gluster-users > > >>> _______________________________________________ > > >>> Gluster-users mailing list > > >>> Gluster-users@xxxxxxxxxxx > > >>> http://www.gluster.org/mailman/listinfo/gluster-users > > >> _______________________________________________ > > >> Gluster-users mailing list > > >> Gluster-users@xxxxxxxxxxx > > >> http://www.gluster.org/mailman/listinfo/gluster-users > > >> _______________________________________________ > > >> Gluster-users mailing list > > >> Gluster-users@xxxxxxxxxxx > > >> http://www.gluster.org/mailman/listinfo/gluster-users > > >> > > > > > _______________________________________________ > > Gluster-users mailing list > > Gluster-users@xxxxxxxxxxx > > http://www.gluster.org/mailman/listinfo/gluster-users > _______________________________________________ Gluster-users mailing list Gluster-users@xxxxxxxxxxx http://www.gluster.org/mailman/listinfo/gluster-users
