KernSafe Technology

Hello,
I have created a server and mirror target with physical partion sizes of 500 GB and created a target by using basic image file 250GB in size with room to expand. Target and mirror working fine. I Expand image file on mirror and then expand image file on main server to 500 GB. IStorage Server reports size as 488 GB on each and seems fine. If I connect with Read only Initiator connection the size is still reported as 250 GB. Now I'm getting an error of a data cyclic redundancy check error when trying to copy files to the main server drive even though the drive is not filled up to even up to the 250 GB size yet. What's going on here? Did I miss something?

Thank You
Larry

After you expended image file size, just like a hard disk become large, but the partition layout won't change, so you need to extend the partitions.
Windows VISTA and newer OS support dynamicly extend partition size.

Thank you. This helps a lot.
A couple of other questions. When creating a mirror on a server, is it necessary for both the originating server and server holding the copy to be standard server or above or can the server receiving the copy be a personal edition? Also, can you discuss at all the process by which the server holding the original mirror target verifies the mirror image is intact. In other words, what happens if both servers are shut down at the same time or the connection is lost as might easily happen accross the internet?

You can use Standard iStorage Server as the first iSCSI mirror device, and use Personal iStorage Server as the second iSCSI mirror device.
The mirror function is a "real-RAID1", once any one of mirror device fail, the whold target (both first mirror device and second mirror device) will not work, that ensure data consistency.
If you nned failover feature (High-Availability), you need Ultimate version.

Thank you.
Can you then explain the procedure for recovery if the main originating device fails? I think I have read most all of the docuements and don't see it. Can the mirror drive be read somehow? I had this happen in a test setup and couldn't find a way to get the data back. My trial license ran out just then and now I can't do anything. I really think it takes more than 20 days to properly test something like this by the way, in case anyone at Kernsafe is interested.

You can log on to the second mirror device directly and get the data when the first mirror device can't work (lost or broken).
We can consider to extend the trial period, thanks for your advice.

Hi Olivia,
I have not been able to do this. Perhaps you can tell me how I may have gone wrong.
Here is my setup.
My main storage is a large Raid 50 array that I am also testing. The usable space is 8 terrabytes. I created a 1 TB partition for testing. I also set up a 1 TB drive on another server (both windows 2003 with new Intel hardware). On the second server I set up a 1 TB hard drive and created a 1 TB basic image target on it. On the first server I created a mirror application and pointed it at the second target. Everything appeared to be OK. The drive sync went ok and I started putting data in the main target. The network activity showed as the new data was being synced. This went on for several days of backup testing. Now at sometime on Sunday my main array failed completely. (not related I'm sure, just some bad hardware) Now when I go to server 2 I cannot get access to the physical drive. Computer management says the drive is healty, but I can't get access to it even with I storage service stopped and server console stopped. If I start the service and console I can connect an initiator to the target, but it does not come up with a drive letter or show in My Computer if I go to Computer management I see the new target disk with 2 unallocated partitions. A small one with 80.42 GB and a large one with 849.95 GB. The actual size of my physical drive partition is 930.38 GB. If I try to do a check disk on the physical drive with Istorage service running I get "Cannot open volume for direct access". If I stop the IStorage service I get "Unable to determine volume version and state". Now unfortunately on the same day and approximate time that this occured my trial on my primary server ran out and I was unable to test anything from that server since it simply wouldn't run. My trial on the second server runs out in 2 days. Would the trial running out have anything to do with not being able to access the target on the second server? Do you think there was something flawed in my original setup that made it look like it was mirroring ok but wasn't? Or is it possible that the drive array failure on the first machine was somehow able to replicate corruption to the second server? I can't think of any other possibilities. I absolutely must be able to mirror this data and recover it or I cannot go forward with my project. Right now I'm planning to format both machines and start a new trial. Set up the similar situation and deliberatly crash it to monitor what happens. But your input before I do this would be very much appreciated. Thank you.

Did you have made a full-synchronization while creating mirror application?
Only this condition you do not need synchronization:
the first iSCSI device and the second iSCSI device is not partitioned and not initialized (no drive signature and no partition table, completely empty, such as new hard disk, new created image disk).

That may have been the problem. I can't remember. I will document my steps from here on. But I think the software should be able to report a problem like this. I'm on hold right now while I set up an entirely new San device and server.