I am fairly new to ISCSI and SAN technology but having recently invested in the technology I am trying to find out exactly what can and can not be manipulated, filesystem wise, without requiring a reboot. I am using the inbuilt software ISCSI initiator and multipathing in CentOS 5.1. My steps so far. Create 10GB volume on SAN # iscsiadm -m session -R # fdisk /dev/mapper/mpath0 # kpartx -a /dev/mapper/mpath0 # mke2fs -j /dev/mapper/mpath0p1 # mount /dev/mapper/mpath0p1 /test-mount <--works fine to here--> Now I want to extend the volume on the SAN to 15GB run fdisk and use resize2fs to extend the filesystem, is this possible without a reboot? Currently, I don't seem to be able to get fdisk to see the new disk size after extending the volume. I know this can be done using LVM if I created 2 volumes rather than extending but I am curious to know if it can be done without LVM. Any other tips about what can be done with ISCSI would be welcome. Thanks Dean
On Thu, 2008-01-31 at 11:40 +0000, Plant, Dean wrote:> I am fairly new to ISCSI and SAN technology but having recently invested > in the technology I am trying to find out exactly what can and can not > be manipulated, filesystem wise, without requiring a reboot. I am using > the inbuilt software ISCSI initiator and multipathing in CentOS 5.1. > > My steps so far. > > Create 10GB volume on SAN > # iscsiadm -m session -R > # fdisk /dev/mapper/mpath0 > # kpartx -a /dev/mapper/mpath0 > # mke2fs -j /dev/mapper/mpath0p1 > # mount /dev/mapper/mpath0p1 /test-mount <--works fine to here--> > > Now I want to extend the volume on the SAN to 15GB run fdisk and use > resize2fs to extend the filesystem, is this possible without a reboot? > Currently, I don't seem to be able to get fdisk to see the new disk size > after extending the volume.ISTR that long ago, "sfdisk -R" would cause a re-read of the partition info and get it imported. You may need to umount the block devices first, and/or turn of LVM (haven't tried it with LVM active). I know it did work, but that was not using LVM and it was on a device that was not mounted anywhere at the time.> <snip>> Thanks > > Dean > <snip sig stuff>-- Bill
On Jan 31, 2008 12:40 PM, Plant, Dean <dean.plant at roke.co.uk> wrote:> I am fairly new to ISCSI and SAN technology but having recently invested > in the technology I am trying to find out exactly what can and can not > be manipulated, filesystem wise, without requiring a reboot. I am using > the inbuilt software ISCSI initiator and multipathing in CentOS 5.1.Without a reboot of the centos, certainly; just restart the iscsi service! Without stopping the iscsi ? Probably, take a look at the iscsiadm manual.> > My steps so far. > > Create 10GB volume on SAN > # iscsiadm -m session -R> # fdisk /dev/mapper/mpath0 > # kpartx -a /dev/mapper/mpath0You dont need to create additional partition, just use /dev/mapper/mpath0 instead of /dev/mapper/mpath1 !> # mke2fs -j /dev/mapper/mpath0p1 > # mount /dev/mapper/mpath0p1 /test-mount <--works fine to here--> > > Now I want to extend the volume on the SAN to 15GB run fdisk and use > resize2fs to extend the filesystem, is this possible without a reboot? > Currently, I don't seem to be able to get fdisk to see the new disk size > after extending the volume. I know this can be done using LVM if I > created 2 volumes rather than extending but I am curious to know if it > can be done without LVM.If you want to do the job without dismounting the ext3 partition, this is an interesting challenge. Because with LVM this is too easy :-)> > Any other tips about what can be done with ISCSI would be welcome. > > Thanks > > Dean > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >-- Alain Spineux aspineux gmail com May the sources be with you