Microsoft Support for iSCSI

March 31, 2004

Published: April 21, 2004

Please note: Portions of this transcript have been edited for clarity

Introduction

Moderator: KenM (Microsoft)
Welcome to today's TechNet Chat. Our topic is Microsoft Support for iSCSI. Questions, comments, and suggestions are welcome.

Moderator: KenM (Microsoft)
We've got 2 iSCSI experts here today to answer your questions. First, I'll Let the hosts introduce themselves.

Host: Suzanne (Microsoft)
Hi, my name is Suzanne Morgan and I am an Enterprise Storage Program Manager in the Windows Core team.

Host: Claude (Microsoft)
Hello, my name is Claude Lorenson and I am a Technical Product Manger on the Windows Server Marketing team

Start of Chat

Host: Suzanne (Microsoft)
Q: When will Microsoft be releasing Target software for ISCSI
A: Microsoft has no plans to release target software for iSCSI

Host: Suzanne (Microsoft)
Q: When will iSCSI be supported with MSCS?
A: The plan for support for iSCSI is currently being worked out. We expect to have more information out in the next month.

Host: Claude (Microsoft)
Q: Does anyone know if server-less backups are now possible or supported by leveraging iSCSI?
A: Serverless backups have not been part of our current series of tested deployments but there is nothing preventing iSCSI to participate in those scenarios....

Host: Suzanne (Microsoft)
Q: if MSCS which one w2k or w2k3?
A: Although iSCSI works very well with both Win2K and W2k3 clusters, Microsoft is only planning to support Clustering with iSCSI on W2k3 server.

Host: Claude (Microsoft)
Q: The March 04 press release officially stated that Exchange 2003 was supported on iSCSI - does that mean that Exchange 2000 isn't?
A: Exchange 2000 and Exchange 2003 are both supported on iSCSI as long as the targets are on WHQL

Host: Suzanne (Microsoft)
Q: how about diskless boot via iSCSI?
A: Microsoft is currently looking at the possibility of supporting iSCSI Network Boot using standard Gigabit ethernet NICs, but do not have firm plans at this time.

Host: Suzanne (Microsoft)
Q: What is WHQL?
A: WHQL is actually the group inside Microsoft that implements the Designed for Windows Logo Program for hardware

Host: Suzanne (Microsoft)
Q: Adaptec has a NIC with I13 support just released - so bootable with W2k
A: Today, we support iSCSI diskless boot as long as you are using an iSCSI HBA that supports boot. lified host bus adapter (HBA)

Host: Suzanne (Microsoft)
Q: So are we to understand that GBE teams with target SW are not considered supported?
A: No, there are solutions that include target iSCSI software that are supported.

Host: Suzanne (Microsoft)
A: The list of qualified iSCSI targets is here: http://www.microsoft.com/windowsserversystem/storage/iscsi.mspx

Host: Suzanne (Microsoft)
Q: Will the issue with dynamic disks and iSCSI be fixed any time soon?
A: We expect this issue to be resolved in an updated volume manager that will be released before Longhorn.

Host: Claude (Microsoft)
Q: Where is there information on supported target SW and GBE pairs?
A: the link provide earlier will have the target software on generic hardware. We are looking into doing a logo program for software target.

Host: Suzanne (Microsoft)
Q: What about support for XP Home?
A: The Microsoft iSCSI Software initiator is supported today with XP Pro, Windows Server 2003, and Windows 2000.

Host: Suzanne (Microsoft)
A: We are looking at supporting XP Home in the future.

Host: Suzanne (Microsoft)
Q: In the MS WhitePaper "Boot From SAN in Windows Server 2003" it state that iSCSI boot from SAN is supported with iSCSI HBAs that support int13. What about diskless boot using this technique?
A: Diskless boot is supported for iSCSI the same way it is supported for fibre channel, it requires the use of an HBA.

Host: Claude (Microsoft)
Q: What is Microsoft's position on Exchange and SQL Server w/iSCSI?
A: Exchange and SQL are supported on iSCSI as long as the iSCSI targets are on WHQL. the support for iSCSI is the same as support for any block based protocol (like FC)

Host: Suzanne (Microsoft)
Q: what about MPIO over iSCSI?
A: Microsoft supports Microsoft MPIO in the next release of the Microsoft iSCSI Software Initiator, Osaka due out at the end of the year.

Host: Suzanne (Microsoft)
A: The beta program for Osaka will be open in late April.

Host: Suzanne (Microsoft)
A: This version will include full Microsoft MPIO functionality. iSCSI vendors will also have Microsoft MPIO solutions for iSCSI available this year.

Host: Claude (Microsoft)
Q: How do ISCSI based clusters compare with SAN based clusters in terms of failover and performance
A: Failover is the same as FC SAN, performance is dependent on the protocol bandwidth. Todau iSCSI is limited to 1 G while FC is 2 G. Load balancing techniques for iSCSI are similar to the ones in FC

Host: Claude (Microsoft)
Q: Are their any whitepapers/benchmarks/suggestions on ip stack configuration to validate the network config for iSCSI
A: Check microsft.com/storage in the next 2-3 weeks for a full deployment guide white paper on iSCSI

Host: Suzanne (Microsoft)
Q: how do we get on the Osaka beta list?
A: Customers and partners can sign up for the Beta by visiting <http://beta.microsoft.com> and registering for the beta using guest ID: iSCSI.(case sensitive)

Host: Claude (Microsoft)
Q: I know this is more a vendor question than an MS one, but are you guys aware of anybody thinking blending IP SAN and NAS in a StorageServer2003 product?
A: Yes...Lefthand Networks has just released a NAS gateway based on Storage Server that is targeted to connect to LeftHand IP SAN, other vendors are in development

Host: Suzanne (Microsoft)
Q: Why would I not just implement a SAN??
A: iSCSI and Fibre Channel SANs complement one another. The real benefit of iSCSI is in its ability to transport block-based storage over any kind of IP network. iSCSI can be used where block storage such as fibre channel is used today.

Host: Claude (Microsoft)
Q: will failover take the same amount of time or more for clusters using ISCSI compared with SAN based solution
A: Additionally, iSCSI extends block based transport over longer distances, so it can be used for remote mirroring, remote backup and similar applications. You can also use iSCSI to build a virtual Storage Area Network using existing Gigabit network

Host: Claude (Microsoft)
A: Our tests indicate similar failover time assuming adequate bandwidth available

Host: Suzanne (Microsoft)
A: iSCSI can perform similar functions which are currently performed by Fibre Channel, except it runs on a more affordable physical equipment, like standard Ethernet. It is also more flexible: it can use any network which supports TCP/IP.

Host: Claude (Microsoft)
Q: With a serious, done right, iSCSI environment, how close am I to implanting a SAN in cost??
A: iSCSI is a SAN, I am assuming how close to a Fibre Channel SAN? This question has a different answer every day as FC gear is coming down in price. Deployment costs are viewed at 20 to 30% cheaper TODAY....

Host: Suzanne (Microsoft)
Q: Where is there basic information explaining how to configure iSCSI. For example what to put in Target LUN, OS Bus and other iSCSICLI commands.
A: There is information in the User's Guide included with the Microsoft iSCSI Software Initiator. There is also information in the Microsoft support for iSCSI whitepaper: http://www.microsoft.com/windowsserversystem/storage/iscsi.mspx

Host: Claude (Microsoft)
Q: LeftHand... right, but the IP SAN product is non-Windows, correct?
A: LeftHand iSCSI target has the Design for Windows Logo. Keep in mind that most iSCSI targets on the Windows Server Catalog are not running on Windows-this is not a requirement to have a target with a logo in the RAID/Storage category.

Host: Suzanne (Microsoft)
Q: What iSCSI configs does Microsoft support?
A: Microsoft supports configs that use a qualified iSCSI target under the Designed for Windows Logo Program + The Microsoft iSCSI software initiator or a qualified HBA under the DFW Logo program.

Host: Suzanne (Microsoft)
Q: When will we see a logo program for iSCSI software target on Windows?
A: We are looking into the possibility of releasing a Logo Program for iSCSI Software targets on Windows - more info next month.

Host: Claude (Microsoft)
Q: I have met with 1/2 dozen enterprise SAN or NAS vendors but they all say ISCSI is not really ready for the enterprise this year, would you agree for mission critical use?
A: All depends on what enterprise ready means. Today you have iSCSI solutions that are ready to go for Exchange, SQL and many backup configurations. In the data center, iSCSI is used to connect isolated server to a SAN-Fibre Channel is legacy in data ce

Host: Suzanne (Microsoft)
Q: When will an issue with tapes over iSCSI with MS iscsi initiator and Veritas backup products be fixed?
A: There are various tape products that support iSCSI today include Computer Associates. There will be more detailed information in the iSCSI Deployment Whitepaper due out in April/May.

Host: Suzanne (Microsoft)
A: I can't comment specifically on the problem Veritas' software is having.

Host: Suzanne (Microsoft)
Q: Can adapter teaming be used on the client-side to increase overall bandwidth to an iSCSI target that has multiple Gbit connections?
A: We support NIC teaming, that happens at the TCP-IP layer below us.

Host: Claude (Microsoft)
Q: Has MS used FalconStor's iSCSI + NAS product for Windows?
A: We will also be supporting multiple connections and load balancing in the Osaka release of the iSCSI initiator.

Host: Claude (Microsoft)
A: Contact FalconStor directly to find out which versions they will make available

Host: Suzanne (Microsoft)
Q: Does Windows backup program work with iSCSI tapes?
A: Yes, also we have tested CA with SpectraLogic native iSCSI tape library.

Host: Claude (Microsoft)
Q: when will there be any case studies on iSCSI be available?
A: We are currently working on quite a few case studies, so in 3-4 weeks they should be posted. In the mean time, Microsoft partners have Windows based case studies on their sites

Host: Suzanne (Microsoft)
Q: Are there any iSCSI Software targets today that we can download for Windows?
A: Yes. www.stringbeansoftware.com has one in beta that they will be releasing soon.

Host: Suzanne (Microsoft)
Q: Does Microsoft support boot from iSCSI?
A: Yes, we support iSCSI boot as long as you are using DFW qualified host bus adapter (HBA)

Host: Claude (Microsoft)
Q: Why the decision not to release Target software??
A: Microsoft feels that there are partners that can better focus on this topic.

Host: Suzanne (Microsoft)
Q: Please expand and provide URL on your statements: “remote mirroring, remote backup.. You can also use iSCSI to build a virtual Storage Area Network"
A: There is more information in the Microsoft support for iSCSI whitepaper and in the upcoming deployment whitepaper

Host: Suzanne (Microsoft)
Q: What is iSCSI especially good for? Any particular scenarios/applications?
A: Storage Server consolidation from DAS to SAN, LAN free backup, Exchange, SQL

Host: Suzanne (Microsoft)
Q: When will iSCSI be supported in Windows 2003 MSCS? How about Win2k MSCS?
A: The plan for support for iSCSI on Server 2003 is currently being worked out. We expect to have more information out in the next month.

Host: Suzanne (Microsoft)
A: Although iSCSI works very well with both Win2K and W2k3 clusters, Microsoft is only planning to support Clustering with iSCSI on W2k3 server

Host: Claude (Microsoft)
Q: what advantages do iSCSI have for storage consolidation of DAS over NAS?
A: iSCSI can run all applications and provide better resiliency and scalability. NAS is used for file and print mostly

Host: Suzanne (Microsoft)
Q: Is iSCSI supported with SQL or is there a separate qual for that?
A: Yes, SQL and Exchange are supported with iSCSI as long as you are using an iSCSI target that has received the Designed for Windows Logo Qualification + the Microsoft iSCSI Software Initiator OR a qualified iSCSI HBA

Host: Suzanne (Microsoft)
A: SQL and Exchange do not have separate qualification programs for hardware, they rely on the Designed for Windows Logo Program to qualify hardware for use with Windows.

Host: Suzanne (Microsoft)
A: If you are using a 3rd iSCSI software initiator, you need to contact the vendor for support.

Host: Claude (Microsoft)
Q: Claude_MS: NetApp has pretty impressive resiliency and scalability. There are other vendors too. Is the advantage limited to Exchange and SQL
A: Leaving vendor specific implementations out-NAS as a category is viewed as less resilient and scalable than block based storage. Exchange for example is not supported on a NAS configuration from NetApp but is supported on their iSCSI target.

Host: Claude (Microsoft)
Q: Where is a place to get good detailed setup configuration examples for iSCSI.
A: From Microsoft point of view, we will have a deployment white paper in the next 2 to three weeks.

Host: Suzanne (Microsoft)
Q: How deep does TQ goes in MS iSCSI?
A: Default is simple tagged, multiple outstanding requests are allowed.

Host: Suzanne (Microsoft)
Q: If Exchange and SQL Server get use the DWL for hardware, what about clustered Exchange and SQL? Not supported yet?
A: Once the program is online for submitting iSCSI qualified Cluster configs to Winqual, those configurations will be supported.

Host: Suzanne (Microsoft)
Q: how many commands does it allow outstanding,
A: 255 requests per lun

Host: Suzanne (Microsoft)
Q: Ken/Claude with the iSCSI version 1.03 iSCSI initiator there were some issues with dynamic disks and shared disks when Windows Server 2003 rebooted. Have these issues been resolved in version 1.03 of the iSCSI initiator?
A: No, the issue with Dynamic Disks affect many more components besides iSCSI - that will be resolved when the next release of Volume Manager is available

Host: Claude (Microsoft)
Q: Will there be another iSCSI Chat, and if so when
A: At the end of the month there will be a developer chat and other will be coming also

Host: Claude (Microsoft)
Q: Jay: I think that was me - and the storage chat was this one!!
A: There are other non iSCSI but storage related chat coming in the next couple of months....

Host: Suzanne (Microsoft)
Thanks everyone for attending !!

Moderator: KenM (Microsoft)
Thanks for joining us today and thanks for the questions. It's time for us to go now.

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