Anchor
example_1 example_1

Example 1: Dual node DSSI cluster with 4 shared disks

To setup two emulated VAX 4000 Model 108 VMs, we need two host machines, preferably running the same version of Windows. 

Assume that these host systems have network host names CASTOR and POLLUX in the host TCP/IP network.

The following are CHARON VM configuration files for the emulated VAX 4000 Model 108 nodes running on CASTOR and POLLUX:

set PAA port[1]=11021 host[1]=”castor:11012”

load HSD50 DISKS dssi_host=PAA dssi_node_id=3

set DISKS scs_system_id=3238746238 mscp_allocation_class=1

set DISKS container[0]="\\DiskServer\Share\dua0-rz24-vms-v6.2.vdisk"
set DISKS container[1]="\\DiskServer\Share\dua1-rz24-vms-v6.2.vdisk"
set DISKS container[2]="\\DiskServer\Share\dua2-rz24-vms-v6.2.vdisk"
set DISKS container[3]="\\DiskServer\Share\dua3-rz24-vms-v6.2.vdisk"
... 

Let's review both configurations step-by-step.

1. The first line of both configuration files establishes parameters for the preloaded "PAA" SHAC host adapter. Only 2 parameters of SHAC are important for us in this situation: 
   

   Parameter	Description
   port	An integer value that specifies the TCP/IP port number on which an emulated SHAC host adapter listens for connections from another emulated SHAC host adapter. Possible port values range from 1024 through 32767.
   host	A string value that specifies the TCP/IP host name (and optional TCP/IP port number) to connect to another emulated SHAC host adapter. The syntax for the string is “host-name[:port-no]” with possible values for "port-no" in the range from 1024 through 32767.

   Thus, CASTOR connects to POLLUX's port 11021 and listens for POLLUX's connection on port 11012,  POLLUX connects to CASTOR's port 11012 and listens for CASTOR's connection on port 11021 
   

   Div
   class pagebreak

   
   

2. The second and third lines of both configuration files are for loading "DISKS", HSD50 storage controllers and its parametrization:

   Parameter	Description
   dssi_host	A string value that specifies the instance name of the emulated SHAC host adapter serving the virtual DSSI network. If this value is not set, CHARON VM tries to locate the host adapter automatically. This automatic lookup works only if the CHARON VM configuration has exactly one instance of the emulated SHAC host adapter.
   dssi_node_id	An integer value that specifies the address of an emulated HSD50 storage controller on a virtual DSSI network. Possible values range from 0 through 7 (initially set to 0). Note that this parameter must be unique for each SHAC and HSD50 instance; for example if 0 and 1 are used as the IDs for differents ports of "PAA" the HDS50 instance cannot use 0 or 1. But it can use 3 for example.
   scs_system_id	A string value that specifies the SCSNODENAME of the emulated HSD50 storage controller. The string can consist of up to 10 characters. Possible characters are uppercase letters: A through Z and integers.
   mscp_allocation_class	An integer value that specifies the ALLOCLASS of an emulated HSD50 storage controller. Possible values are from 0 through 255 (initially set to 0). Warning Note that the MSCP allocation class must be the same as the allocation class of the VAX node. For nodes it is set using MODPARAMS.DAT and AUTOGEN Refer to OpenVMS User's Guides for details

   
   

   Warning
   In both configuration files, the names of the emulated HSD50 storage controller "DISKS" must be identical. Not following this rule can cause data corruption on the (virtual) disks.

   
   

3. The last lines demonstrate mapping "DISKS" HSD50 storage controller to disk images, shared between both hosts. A "container" parameter is used for this purpose. This example assumes that all disk images are accessible from both host machines via Microsoft share or some other realization. It is also possible to create a network drive and use it in the CHARON VM configuration files abobe.

Anchor
example_2 example_2

Example 2: Triple node DSSI cluster with multiple iSCSI disks

In this example we assume that all three host systems have an iSCSI initiator and are connected to a common iSCSI server. The iSCSI disk server provides 8 virtual disks with R/W access on all hosts. These disks are configured as "\\.\PhysicalDrive0" to "\\.\PhysicalDrive7" on each of the host machines.

The storage configuration must be identical on all three nodes. It is recommended to describe the storage structure in a separate configuration file to be included in each CHARON VM configuration file with the use of the "include" instruction (name of the configuration file set to "disksets.cfg" in this example) and store it on a common network share ("\\DiskServer\Share"):

CHARON VM configuration file for the emulated VAX 4000 Model 108 node running on HOST001 is as follows:

include \\DiskServer\Share\disksets.cfg
... 

CHARON VM configuration file for the emulated VAX 4000 Model 108 node running on HOST002 is as follows:

CHARON VM configuration file for the emulated VAX 4000 Model 108 node running on HOST003 is as follows: