Ever ask yourself what you could do with a sixpack of beer, two servers, a bunch of data drives, and a collection of parts?
Some of the following examples are based on a 9577 as a server. Note that the 85/95 series can use up to EIGHT SCSI adapters (NOT under W95 or Win 3.1x!).
Still rooting for details on the software needed to run things in target mode.
Hacking NT4 Workstation for Fault Tolerance
Hacking NT 4
Workstation for Fault Tolerance
So you are bored. Significant other is gone for a while.
No beer (or wine) in the fridge. Its dark, you're wearing sunglasses...
This system has the programs, data and system files all on one disk.
It cannot perform any special tasks like disk mirroring or duplexing.
All disks are attached to one SCSI controller, with the data being mirrored
on the Primary and the Mirror drives. If the single controller fails, all
data is inaccessible.
Disk duplexing is like Disk Mirroring, but each hard drive has it's
own controller. This example shows an external drive being mirrored. Duplexing
provides more fault tolerance than Mirroring because either drive or controller
can fail and the data is still accessible.
Fault tolerance can be increased by using disk duplexing. Duplexing allows you to access the data in the event of a disk or adapter failure
You can turn off a storage enclosure and replace the hard drive without
turning off the computer.
Three of the four 3511 SCSI External Storage Enclosures contain seven SCSI hard drives. The fourth storage enclosure only has six SCSI hard drives because it's SCSI Adapter also supports the System Disk.. This example is for IML systems that require a System disk. A non-IML system could dispense with the system disk and use seven drives in each 3511.
In this example, one SCSI adapter in each computer is attached to the shared set of six 3510 SCSI Storage Enclosures. The other SCSI controller is attached to the system hard disk.
NOTE the SCSI IDs for the shared disk set- the two SCSI controllers attached to the disk set have different SCSI IDs (ID 7 and ID 6). Also, the IDs for each SCSI device involved with this disk set range from 0 to 7. NO DUPLICATE IDs ARE ALLOWED!!!
My question- Do you only terminate the adapters? Sure can't terminate any of the drives..
In this example, both systems are attached to a set of SCSI disks in 3510 Enclosures. In both systems, the same SCSI adapter that is attached to the disk set also is attached to the system disk. NOTE that all devices connected to the disk set have SCSI IDs between 0 and 7.
NO DUPLICATE IDs on SCSI devices
attatched to the disk set allowed!
It seems that only the system disks have termination enabled. On IML systems, this setup REQUIRES the 44/45 SCSI BIOS and the enhanced complex BIOS (T1 and T2 need upgrade EPROM!). Note the SCSI adapter at ID6 and a system disk at ID4.