Buffalo iSCSI Instructions for use

Best Practices for running Buffalo
Technology iSCSI platforms on VMware
vSphere

Summary of steps you should take to insure that you have a trouble free setup:
• Make sure that you have unique names for all your LUN’s. This is required if you have more than
one iSCSI unit or the additional LUN’s will not be re ognized by ESX.
• For ea h LUN that you make, set the Maximum Conne tions field in Advan ed Settings to the
total number of ESX servers that will be atta hed to the LUN. Example: For 5 servers, set
Maximum Conne tions to 5.
• Make all of your arrays’ LVM/LUN onfigurations in the TeraStation before atta hing them to
your ESX server. On e they are made, you annot hange them due to a limitation in the
urrent firmware 1.32 / 1.40. Making a hange after onne ting to the ESX server requires
rebuilding the arrays and losing all data.
• Our iSCSI units are best onne ted to your environment with only LAN 1 plugged into your
swit h. Do not use LAN 2 as your only onne tion to the host server. Our units do not support a
network failover onfiguration.
• Before making hanges to your iSCSI TS’s settings, first stop the iSCSI servi e in the TeraStation
Web Administrator interfa e. Do not stop the iSCSI servi e if the unit is a tively being used with
your ESX server.
• Change the time zone to your lo al zone.

Simple Configuration (one ESX server and one TS III iSCSI of 4 TB apa ity or
less)
Requirements:
OS: VMware ESX 4.0, 4.1
iSCSI Firmware: 1.32 or greater
Re ommend array onfigurations:
These are the most ommon ways to set up a unit with 4 TB or less of spa e.
Raw Capacity RAID Level Number of Arrays
2 TB 5 1
0 1 or 2
1 1 or 2
4 TB 5 1
0 1 or 2
1 1 or 2
Note: Max 4 TB unit / No LVM (If you need more than two LUNs use omplex onfiguration)

The simple onfiguration method is easy to use and qui k to onfigure. When you take the unit out of
the box, onfigure it before onne ting it to the VMware ESX server.
1. Make sure that the iSCSI Servi e is turned off.
2. Set the time to your time zone. NPT is re ommended.
3. Hook up your UPS and onfigure it under Maintenan e -> Power Management
4. VMware allows a maximum 2 TB LUN size, so remember this when you de ide what disk and
volume layout you want.
5. When all onfigurations are finished, turn the iSCSI Servi e ba k on.
Complex Configuration (two or more ESX servers or a TS III iSCSI with apa ity
greater than 4 TB)

Requirements:
OS: VMware ESX/ESXi 4.0, 4.1
iSCSI Firmware: 1.32 or greater
Re ommend array onfigurations:
These are the most ommon ways to set up a unit with 6 TB or more of spa e.
Raw Capacity RAID Level Number of Arrays
6 TB 5 1
0 1 or 2
1 2
8 TB 5 1
0 1 or 2
1 2
Note: For 6 TB or larger you must use LVM.

Starting up a system su h as this will take more onfiguration than our simple setup. When you take the
units out of the box, onfigure them before you onne t them to the VMware servers.
1. Make sure that the iSCSI Servi e is turned off.
2. Set the time to your time zone.
3. Hook up your UPS and onfigure it in Maintenan e -> Power Management.
4. Turn on the Logi al Volume Manager.
5. Add your volumes. Please keep in mind these few points when you are making ea h volume:
a. Make sure that ea h volume name is unique a ross all iSCSI units in your environment.

b. In advan ed settings set to the number of servers you will be atta hing these units to in
the field “Max Conne tions”. The maximum number of servers that an be atta hed is
16.
. Keep in mind that you are only allowed 32 Logi al Volumes on the unit.
d. VMware allows a maximum 2 TB LUN size, so remember this when you de ide what disk
and volume layout you want.
6. After onfiguration is finished, turn the iSCSI Servi e ba k on.
Notes:
o Power up and power down sequen e:
 Please make sure that you power on the iSCSI units first before the ESX servers.
 When powering down, shut down the ESX server first, then the iSCSI TS III units.
 Never dis onne t the LAN able while the system is a tive.
o Buffalo Te hnology strongly re ommends onne ting your iSCSI TeraStation to UPS
power. We re ommend the APC Smart-UPS models. Runtime should be onfigured to
ex eed the runtime of the ESX server to prevent the storage array powering down
before the server.