Spring Switzerland GmbH Ver. 1.61 manual Using snapshot with Open-E iSCSI

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Using snapshot with Open-E iSCSI

Usage snapshot facility heavily depends on the initiator of software support for dynamic units* and the partition scheme which you use on the operating system where you attach the targets. The most common error is if on the client side that uses an LVM/LVM2 (Linux) scheme or Microsoft's Dynamic Disks which connect to the snapshot and original volume from the same client malfunctions. This is due to the fact that normally an LVM volume bares special metadata which is used as the identify information and since a snapshot simply doubles those metadata it can confuse your partitioning software (for example logical volume manager sees two identical volumes).

In order to take proper advantage of Open-E iSCSI Target's snapshot technology the volumes your Open-E iSCSI Target exports should be imported in your operating system as Basic Volume (Windows) and you should not incorporate them as logical volumes in LVM/LVM2 (on Linux) if you plan to use snapshots and access them from the same machine at the same time.

If you plan to take snapshots and import them alongside the original volume - access them from the same client. Below is instruction how to import a target in a Microsoft basic volume:

a.Create target volumes (tgv),

b.Create a target in Open-E iSCSI,

c.Add chosen volumes to the target.

d.In MS iSCSI Initiator add Open-E iSCSI Target as an iSCSI portal in the MS iSCSI Initiator console,

e.Log onto the target,

f.Open the computer management,

g.Select the disk management,

h.Add the volumes as basic disks,

i.On Open-E iSCSI Target create snapshots: setup Æ target manager and reserve desired space for snapshots (reserve about 5-20% of total space for the snapshots). Determine number of snapshots, assigned to the volumes and distribute the reserved space as needed. To activate a snapshot go Maintenance Æ Snapshot.

j.Follow the steps e-h to log and attach the snapshot target.

*) Currently iSCSI Microsoft Initiator ver1.06 does not support dynamic volumes.

The best solution to use snapshots without decreasing Open-E iSCSI performance is to assign separate RAID. This RAID will be optimized for a writing speed (e.g. few disks in RAID 0 only for snapshots). Follow the steps below:

a.Add RAID chosen for data as NEW (Vg0) in the menu WebGui: setup Æ target manager Æ Volumes,

b.Create one or more Tgv’s. At this point, there is no free space reserved for snapshots,

c.Add the second RAID to existing Vg0, intended for snapshots, (RAID previously configured as RAID 0),

d.Now only reserve all available space for snapshots.

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Contents Manual Ver .61 May 02 Description of functions Hardware installationConfiguration Before you get startedTroubleshooting Guide Appendix a Appendix B Copyright TrademarksDisclaimer Content of this package Before you get startedSystem requirements Required tools Safety precautionsSupported clients Supported network protocolsDescription of the functions FeaturesWhat is iSCSI? Why Open-E iSCSI?RAID types Hardware installation Installing Open-E iSCSIGetting ready Page Configuration Basic configuration of the iSCSI computerFirst-time operation of Open-E iSCSI Logging into Open-E iSCSI Enterprise Page Create RAID Units Adding Disk Units Creating iSCSI targets volumePage Configuring end user workstation How to connect iSCSI in Windows 2000/XP/2003 Description of functions Server Functions of Open-E iSCSI via browser accessF1, F2 and F5 Shutting down and restartingNetwork Function Language SettingsSet bonding Function IP addressFunction Ipsec Function BondingAdministrator MiiPrimary Function Administrator Access Function Administrator PasswordFunction E-mail notification How to retrieve information from SNMP? Function SSL Certificate AuthorityFunction USE Snmp You can get information by Function Remote accessHardware Function UPS configuration Function Clock settings Target Manager Function Unit Manager Function Power button settingsFunction Set time Function Motherboard infoFunction iSCSI Volume Manager Function Disks LocalizerFunction Units Assigned Function Number of snapshots Function Snapshot definition Function Create new target Function Chap User Target AccessFunction Target IP Access Function Target Volume ManagerFunction Chap User Target Snapshot Access Function Target RenameFunction Target Remove Function Target Snapshot Access Function Snapshot renameFunction Create new Chap user Function Delete Chap user Function Edit Chap userUsing snapshot with Open-E iSCSI Shutdown Function System Shutdown Function Schedule for shutdownFunction System Restart Function Connection reset SnapshotMiscellaneous Software Update During update from CD please follow this steps Function Update downloaderFailed 2.5 S.M.A.R.T Function S.M.A.R.T. e-mail notificationHardware Page Function S.M.A.R.T. unit’s health status 3.3 S.M.A.R.TFunction S.M.A.R.T. info Function 3ware administrations Function S.M.A.R.T. test4.1 H/W Raid Function Create new S/W RAID unit Function Qlogic administrationFibre Channel 4.3 S/W RaidAvailable Raids RAID 6 layout parity-algorithm RAID 5 layout parity-algorithmFunction S/W RAID E-mail notification RAID Function „ManagerFunction „Software RAID unit remove Function „InfoPage Error passwords do not match Troubleshooting GuideOpen-E iSCSI does not boot, keyboard LEDs are flashing Error values are not validIntellectual Property Rights Appendix aOpen-E Software License agreement Ownership and CopyrightWaiver Authorized ServiceDisclaimer of Warranties Limitation of LiabilityGNU General Public License Appendix BPage Page Page Page Page No Warranty How to Apply These Terms to Your New Libraries
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