From CSCWiki
Jump to navigation Jump to search

As of 2013, the CSC has a NetApp FAS3000 series which is capable of hosting network shares. It was donated to us by CSCF. It is also pretty old.


All the manuals are hosted in ~sysadmin/netapp-docs/

Relevant docs for storage modification are: smg.pdf, sysadmin.pdf

iSCSI documentation is in ontop/bsag.pdf


While the NetApp supports both NFS and CIFS, neither of these export options provide the versatility nor the options we desire of a network fileshare. Instead, we have configured the NetApp to export iSCSI block devices to be mounted on aspartame. Therefore, aspartame now replaces ginseng as being the primary fileserver in CSC.


Configuration mechanisms are accessible either via SSH or serial interface, but through aspartame only. The NetApp is not visible on 134net at all.

The private IP is, only available from aspartame on the interface with IP You may have to remove the default route from the routing table in order to successfully contact the machine with ssh.


Should aspartame get totally hosed, or stability is long enough such that all sysadmin folk at the time have graduated, here is how to set up iSCSI on the NetApp+aspartame.

NetApp Configuration

This section describes how to create a volume on the NetApp and export it as an iSCSI target. For further NetApp configuration instructions, refer to the NetApp documentation.

One-time Configuration

Enable iSCSI and configure default authentication.

options iscsi.enable on
iscsi nodename
iscsi security default -s CHAP -p yoursecurepassword -n psilodump

where yoursecurepassword is more secure. For iSCSI hosts, the target will be on node with username psilodump and password yoursecurepassword.

Setting up a new disk aggregate, volume, and LUN

1. Login to the NetApp. You'll either need access to the physical serial console or to ssh as root to psilodump's private IP ( Credentials are stored in /users/sysadmin .

2. To get information on the available disks, run the command:

aggr status -r

This command will return three lists: Active aggregates with their assigned disks, spare disks, and disks managed by the partner. An aggregate is roughly equivalent to an LVM volume group: It is a collection of physical disks, possibly across multiple disk shelves and with various RAID levels applied, which may host one or more logical volumes. Do not proceed if there are fewer than three spare disks of each type available. Refer to the NetApp documentation to add more disks or release disks from existing aggregates.

3. Choose a list of disks for your new aggregate. The available space will be approximately 2/3 of the total disk space.

4. Create the aggregate as follows:

aggr create aggrN -t raid_dp -d [disk-list]

where [disk-list] is a list of the form AA:BB CC:DD ... containing the identifiers for the disks you wish to use to create the aggregate.

5. Retrieve the aggregate information. You will need to know the available space for the next step.

aggr show_space aggrN

6. Create a volume in the aggregate:

vol create volNfoo -s volume aggrN XXXK

where XXX is the total available space in aggrN. You may need to choose a smaller number due to hidden size constraints and rounding. If you can't seem to find the right size, pick one much smaller, and then use the command

 vol size volNfoo +XXX

to grow the volume. This command will tell you how much available space remains, unlike `vol create`, so you don't need to keep guessing.

7. Disable snapshotting and access time update. Neither will be needed for exporting an iSCSI LUN.

vol options volNfoo no_atime_update on
vol options volNfoo nosnap on
snap reserve volNfoo 0

8. Create a LUN on your volume:

lun create -s XXXK -t linux /vol/volNfoo/lun0

where XXXK is the amount of available space on the volume, as shown by the command df.

9. Create an iSCSI initiator group and add all of your hosts to it:

igroup create -i -t linux volNfoo_group
igroup add volNfoo_group
igroup add volNfoo_group

The node identifiers given to the igroup add command will soon be able to access the iSCSI LUN you created above.

10. Map the LUN to the iSCSI initiator group:

lun map /vol/volNfoo/lun0 volNfoo_group

You're done! Any host in the initiator group should now be able to access the LUN you've created as a block device.

aspartame Configuration

Install open-iscsi:

apt-get install open-scsi

Edit /etc/iscsi/iscsid.conf:

node.startup = manual

Start open-iscsi service:

service open-iscsi start

Scan for iSCSI devices from the NetApp:

iscsiadm --mode discovery --type st --portal psilodump

This should dump out a ton of information, for example:


The .130 IPs correspond to one filer, and the .131 IPs correspond to the other filer. Currently we are only using one of the filers (psilodump).

This also populates the /etc/iscsi/nodes/ directory with all possible ways to access the NetApp. For testing purposes (i.e. node.startup = manual), this is okay.

Test to see if you can get the iSCSI device to show up correctly:

iscsiadm --mode node --targetname ""  --portal --login

This should produce output similar to:

Logging in to [iface: default, target:, portal:,3260]
Login to [iface: default, target:, portal:,3260]: successful

Check /dev/disk/by-path/ip* to ensure new disks show up:

# ls -l /dev/disk/by-path/ip*
   /dev/disk/by-path/ -> ../../sda
   /dev/disk/by-path/ -> ../../sda1
   /dev/disk/by-path/ -> ../../sdb
   /dev/disk/by-path/ -> ../../sdb1

If this fails, check all your configuration again.

If this succeeds, you are now ready to try autoconnecting the iSCSI device.

Delete all extraneous entries from /etc/iscsi/nodes/ . This prevents the startup script from (a) hanging, and (b) being very upset. All that is left should be the interface you intend to connect through:

# ls -l /etc/iscsi/nodes/,3260,2000

Edit /etc/iscsi/iscsid.conf:

node.startup = automatic

For the init.d script to work correctly (i.e. properly mount things) we need to add a sleep to allow the device to settle: Edit /etc/init.d/open-iscsi roughly around line 127 to add a "sleep 1":

       # Now let's mount
       sleep 1
       log_daemon_msg "Mounting network filesystems"
       if mount -a -O _netdev >/dev/null 2>&1; then
       log_end_msg $MOUNT_RESULT

Now we can restart the service:

service open-iscsi restart

Now you can configure partitions and mountpoints.

Other notes

Transferring old files from ginseng

Method A

  • On ginseng, use parted to set up the mounted iscsi drive as an ext4 primary partition (setting up a partition of size >2TB requires care and a GPT)
  • Compiled star in /root on ginseng
  • Transferred files with the following Makefile (assuming original user directories in /export/users, destination volume in /mnt/iscsi, make -j8):
foo := $(wildcard /export/users/*)
bar := $(patsubst /export/users/%,/mnt/iscsi/%,$(foo))
all: $(bar)
/mnt/iscsi/%: /export/users/%
	# echo $@ $<
	~/star-1.5.2/star/OBJ/x86_64-linux-cc/star \
	    -copy -p -acl artype=exustar \
	    -C /export/users $(notdir $<) /mnt/iscsi

Method B

  • On ginseng, authenticate with iSCSI target ( lun0).
  • Umount /dev/mapper/vg0-users
  • Copy users filesystem directly to iSCSI target:
dd if=/dev/mapper/vg0-users of=/path/to/psilodump:lun0 bs=8M
  • Resize users filesystem on destination partition to fit:
resize2fs /path/to/psilodump:lun0

Exporting Kerberized NFS from Debian Sid

The default kernel in Debian sid (stable, 2.6.32) does not support the necessary crypto suites to export kerberized NFS to newer kernels. You MUST upgrade the kernel, nfs-common, and nfs-kernel-server packages to AT LEAST squeeze-backports.

iSCSI block device mount optimizations

tmyklebu made some changes to /sys/block/sda/queue. The following is now in /etc/rc.local on aspartame:

echo 2048 > /sys/block/sda/queue/read_ahead_kb
echo 32768 > /sys/block/sda/queue/max_sectors_kb
echo 4096 > /sys/block/sda/queue/nr_requests
echo noop > /sys/block/sda/queue/scheduler

We should increase the iSCSI configs node.session.queue_depth and node.session.cmds_max during next maintenance window.

Disk information

  • shelf 1
    • 14x136GB 10,000RPM FibreChannel disks
    • Currently disconnected, could be connected to psilodump or directly to another machine.
  • shelf 2
    • 14x136GB 10,000RPM FibreChannel disks
    • Currently assigned to psilodump
  • shelf 3
    • 14x500GB 7,200RPM ATA disks
    • Currently assigned to psilodump
  • shelf 4
    • 14x500GB 7,200RPM ATA disks
    • Currently assigned to psilodump


  • aggr0
    • Root aggregate volume, in RAID-DP
  • aggr1
    • Music aggregate volume, in RAID-DP
  • aggr2
    • Users aggregate volume, in RAID-DP
  • aggr3
    • Backups volume for CSC videos, in RAID-DP


  • /vol/vol0
    • Root volume.
  • /vol/vol1music
    • Music volume. This volume is not accessible via NFS or CIFS. It contains only the iSCSI LUN /vol/vol1music/lun0 .
  • /vol/vol2users
    • Users volume. This volume is not accessible via NFS or CIFS. It contains only the iSCSI LUN /vol/vol2users/lun0 .
  • /vol/vol3backup
    • Backup volume for videos. This volume is not accessible via NFS or CIFS. It contains only the iSCSI LUN /vol/vol3backup/lun0 .


aggr status -r aggr<num>
  Shows aggregate status
disk show -v
  Shows disks, and which filer they are owned by (currently all by psilodump)
  storage related things
disk assign
  Assigns orphaned disks to a filer
  Volume stuffs


  • RAID-DP - Double Parity RAID4