一个iSCSI的超廉价双机方案，兄弟们看看可行不？(IBM+DLINK)

freebug

又查了一下资料，汗

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Microsoft Server Cluster (MSCS)
Microsoft MPIO and the Microsoft iSCSI DSM can be used with MSCS. 3rd party DSMs based on Microsoft MPIO which are qualified under the Designed for Windows Logo Program are supported at the same level as the Microsoft iSCSI DSM is supported.    This category maps to Raid System, bustype=iSCSI.  On Windows 2000 only the failover load balance policy is supported.    Although the Microsoft iSCSI Software Initiator works with MSCS on Windows 2000 Server, Customers requiring the support of iSCSI with Microsoft Cluster Server should use either Windows Server 2003 or Windows Server 2008. Please see this link for more information:  
http://www.microsoft.com/windows ... i/iscsicluster.mspx  Microsoft Cluster Server solutions using the Microsoft iSCSI Software Initiator do not required that the configuration be specifically Logo’d in order to be supported.   Customers simply need to use components which are logo’d within their individual device and system categories including NICs, Servers, etc for cluster configurations.  Enterprise class NICs should be used for iSCSI configurations (this applies to MSCS & non MSCS environments).  It is recommended that customers use the Microsoft Cluster Configuration Validation Wizard to validate their iSCSI cluster configurations. This tool is available for download from http://www.microsoft.com/downloads
        Search on the phrase “Microsoft Cluster Configuration Validation Wizard”
Microsoft Server Cluster (MSCS) shared storage when using only a single data path (including the quorum disk) can be implemented using iSCSI disk volumes as the shared storage so long as the iSCSI target supports the SCSI RESERVE and RELEASE commands. There is no special iSCSI, cluster or application configuration needed to support this scenario. Since the cluster service manages application dependencies, it is not needed to make any cluster managed service (or the cluster service itself) dependent upon the Microsoft iSCSI service.
On Windows 2003, all other load balance policies are supported if the iSCSI target supports SCSI PERSISTENT RESERVE and PERSISTENT RELEASE and the persistent reserve key is established on all nodes of the cluster. To configure the persistent reservation key for your cluster, you need to assign 8 byte keys to all nodes in the cluster. Pick a 6 byte value that is specific to that cluster and a different 2 byte values for each node in the cluster.  The cluster specific value should be different for different clusters on your SAN to protect a cluster from using the wrong storage device.
To configure the persistent reservation key for your cluster:
1.        Select an 8-byte value that is unique to that cluster.
2.        Locate the following registry key:
HKLM\System\CurrentControlSet\Services\MSiSCDSM\PersistentReservation
3.        Add the following values:
a.        UsePersistentReservation        REG_DWORD                1
Setting this value to 1 enables Persistent Reservation.
b.        PersistentReservationKey        REG_BINARY                <PR key>
This is a 8-byte binary value that is unique to the cluster. The same binary value must be used on all nodes in the cluster.
Note:        These registry values must be added to all nodes in the cluster.
<PR Key> is an 8 byte binary value that is composed of a 6 byte part that is specific to the cluster and a 2 byte part that is specific to the node. For example if you have a three node cluster you could assign 0xaabbccccbbaa as the cluster specific part. The nodes could then have the following PR keys:

Node 1: 0xaabbccccbbaa0001
Node 2: 0xaabbccccbbaa0002
Node 3: 0xaabbccccbbaa0003

NOTE: In some configurations, failover and recovery of cluster disk resources may not function properly without the persistent reservation configuration mentioned above, even when used with the Fail Over Only load balance policy. In these instances, during disk arbitration, the surviving node of the cluster may be unable to gain access to the disks, and the following errors are listed in the Cluster.Log file.

To prevent this behavior the persistent reservation key will be required even with fail over only in these configurations:

00000928.00000958::2008/11/12-23:24:40.270 INFO Physical Disk <Disk Q:>: [DiskArb] Arbitrate for ownership of the disk by reading/writing various disk sectors.
00000928.00000958::2008/11/12-23:24:40.270 ERR  Physical Disk <Disk Q:>: [DiskArb] Failed to read  (sector 12), error 170.
00000928.00000958::2008/11/12-23:24:40.270 INFO Physical Disk <Disk Q:>: [DiskArb] We are about to break reserve.
00000928.00000958::2008/11/12-23:24:40.270 INFO Physical Disk <Disk Q:>: [DiskArb] Issuing BusReset on signature 30f21b55.
00000928.00000958::2008/11/12-23:24:40.270 ERR  Physical Disk <Disk Q:>: [DiskArb] BusReset completed, status 1.
00000928.00000958::2008/11/12-23:24:40.270 ERR  Physical Disk <Disk Q:>: [DiskArb] Failed to break reservation, error 1.
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freebug

上面摘录M$的iSCSI Users Guide
从这句来看，好像只需要用M$的软件就可以支持MSCS on iSCSi了？

1.Microsoft MPIO and the Microsoft iSCSI DSM can be used with MSCS.

2.Microsoft Server Cluster (MSCS) shared storage when using only a single data path (including the quorum disk) can be implemented using iSCSI disk volumes as the shared storage so long as the iSCSI target supports the SCSI RESERVE and RELEASE commands. There is no special iSCSI, cluster or application configuration needed to support this scenario. Since the cluster service manages application dependencies, it is not needed to make any cluster managed service (or the cluster service itself) dependent upon the Microsoft iSCSI service.

冬瓜头

那个资料所谓的scsi3，并不是说scsi3 reservation。scsi3的reservation是scsi2 reserv的进化版，专为并行多客户端访问lun而生，mscs是一种ha，而不是并行访问。mscs用的是scsi2 reservation，也就是传统的reserve和release command。break reserve是要由客户端也就是主机端来实现，主机不release，reserve永远存在，scsi2时候只要存储端的scsi stack重新reset或者设备断电重启后，即release，scsi3中简单的reset或者reboot并不能release。

freebug

冬大：

>那个资料所谓的scsi3，并不是说scsi3 reservation。scsi3的reservation是scsi2 reserv的进

scsi3 reservation是向下兼容scsi2  reservation的么？
>化版，专为并行多客户端访问lun而生，mscs是一种ha，而不是并行访问。mscs用的是scsi2 res

>ervation，也就是传统的reserve和release command。break reserve是要由客户端也就是主

这里的break reserve是指SCSI3中的么？
>机端来实现，主机不release，reserve永远存在，scsi2时候只要存储端的scsi stack重新reset

>或者设备断电重启后，即release，scsi3中简单的reset或者reboot并不能release。

是不是说SCSI3中的reservation是靠主机完成，SCSI2中是由存储端完成？

冬瓜头

向下兼容。
scsi2和3都有break概念，3中设计概念有变化，是采用regist和eject的方式，多个客户端都可以同时访问，某客户端可以踢出其他所有客户端的注册，这叫做KO，哈哈。
scsi2和3的reservation全部都是靠主机完成，上面说的很清楚了。“break reserve是要由客户端也就是主机端来实现”

mike79

原帖由 freebug 于 2009-8-24 09:20 发表
冬大：

>那个资料所谓的scsi3，并不是说scsi3 reservation。scsi3的reservation是scsi2 reserv的进

scsi3 reservation是向下兼容scsi2  reservation的么？
>化版，专为并行多客户端访问lun而生，mscs是一 ...

disk reserve就是一把锁，避免无序访问导致的数据不一致。访问存储前获取锁，访问后释放锁。通常都是由获取锁的主机释放锁，但是一旦主机掉电了，就要有集群中的备机释放锁，就是break disk reserve。
对于SCSI-2的disk reserve，主机通常通过release释放，而备机释放时通过lun reset/target reset来释放锁。
对于SCSI-3的PR，reset就没用了，备机用preempt and abort命令来释放。因此这两种锁本质上是不兼容的
对于scsi-2的disk reserve，存储重启的话reserve也不存在了，而scsi-3的PR即使掉电也可以继续存在
无论哪种reserve，都需要主机/备机和存储交互才行。如果存储对SCSI协议的实现有问题的话，可能就会导致切换时候出问题。

bbjmmj

原帖由 freebug 于 2009-8-22 01:26 发表
一个iSCSI的超廉价双机方案，兄弟们看看可行不？(IBM+DLINK)


硬件配置：

IBM X3650 服务器 *2
Intel 9400PT PCI-E 千兆网卡 *2
DSN-1100 ISCSI网络存储阵列 *1
Lenovo-network 8口 千兆交换机 *1
5 ...

这玩意如果不支持WINDOWS群集的话，也不用指望卖出去了。
你那个DLINK的盘柜好贵呀，如果可以不考虑容灾的话，建议改用IBM低端SAS盘阵，跟IBM直接订货，都给你安装调试好了，不用你自己动手，也不用怕不支持，这么做可以省不少钱，省不少事。