Would like to buy 3 licenses, but concerned....

[aladdin™]

Originally Posted by Froggie

Dangerous! SHIELD is very important to a successful operation of Rollback, positioning it anywhere but at the top of that list is risky, unless extensive testing (like we did with PHYLOCK) is done.

Dearest Froggie,

The above is on my mind since day one, since you posted the above. I was waiting till I get some experience and then post this and other things you mentioned. As I said earlier, I have lot to digest what you have written about and taken the time to write the above thus teaching me. I also said, that I will read and read your posts again and again to fully digest what you have written.

Any program which installs upper filters and installed subsequent to installing Rollback Rx, puts itself above "Shield.sys". For example, if I have Acronis True Image (ATI) installed, then I install Rollback Rx, I have no problem so far.

But, if I want to update ATI with the latest version, I have to uninstall first the older version of ATI and then reinstall the current version of ATI, while Rollback Rx is now installed.

This will definitely put the ATI upper filters over "Shield.sys". The question is, how does Rollback Rx protect itself that the "Shield.sys" always remain on top, that it is the first upper filter?

For the novices users like me who don't know very much about registry and upper filters?

Kindest regards,

aladdin.

[Owl]

I would suggest the 'stack' principle applies here: anything which fiddles with MBR and low-level drivers must be operated on at its own level in the stack, thus to install ATI and then install RbRX (to get the right priorities), any maintenance on ATI would first require uninstallation of RbRX to be safe.

[aladdin™]

Originally Posted by Owl

I would suggest the 'stack' principle applies here: anything which fiddles with MBR and low-level drivers must be operated on at its own level in the stack, thus to install ATI and then install RbRX (to get the right priorities), any maintenance on ATI would first require uninstallation of RbRX to be safe.

Dear Owl,

But as a novices user of the computer, the above is gibberish for me. There are lots of programs which install themselves in upper filters. And, I am not aware of these as a regular user.

The reason I become aware of this, because if I install first Rollback Rx, and then install O&O Disk Image and BestCrypt I have no problem them co-existing with Rollback Rx, as the filters of these are above "Shield.sys".

However, if I uninstall Rollback Rx and reinstall Rollback Rx, then "Sheild.sys" becomes the first and topmost filter in the upper filters. Now these two programs cannot co-exist with Rollback Rx anymore.

The thread was about these two programs not co-existing with Rollback Rx and Froggie pointed out the above, about the upper filters. Before, Froggie pointing this out, I was not aware of upper filters.

Again, the question remain, how does Rollback Rx protect itself that the "Shield.sys" always remain on top, that it is the first upper filter?

For the novices users like me who don't know very much about registry and upper filters?

Best regards,

aladdin.

[nexstar]

Aladdin, HDS give very strong warnings about encryption software in their knowledgebase article here. They also spell out the procedure for testing out such software without going into complications as to the underlying reasons.

As far as the excellent tutorial goes provided by froggie on this, you need to remember that the purpose of the exercise is to 'hot image' a RollBack system including all snapshots. This is a procedure which officially, as far as HDS are concerned, isn't even possible. So, there is really no reason why RB should have a mechanism to ensure the order of the upper filters.

Use it in the way HDS describe and you don't need to mess with the registry at all. Under these circumstances there may be software which conflicts with RollBack but then that's why they provide a fully working demo.

If you are at all out of your comfort zone editing the registry then it really is best left alone.

Edit: Also, I personally wouldn't feel comfortable using disk encryption with RollBack. If I really needed disk encryption then I think I'd be inclined not to use RB.

Graham

[aladdin™]

Dear Graham,

Thank you for your reply and the link. I am with you about encryption software, such as Bitlocker and BestCrypt. I am not into encrypting drives, and if I wanted too, I cannot, this is based on how I have set up my system. In Windows 7, if one wants to use Bitlocker and such software, then one needs 100mb system partition, as one cannot encrypt mbr and bcd store in encrypted partition.

I have done away with 100mb system partitiion, and moved my mbr and bcd store under the main system partition C, so that I only protect one partition under Rollback Rx, rather than two separate partitions.

I was using BestCrypt on drive D to encrypt some of the important files. But this is not important.

What is important are following:

1. According to Froggie, "Sheild.sys" should be the first and topmost filter in the upper filters.

2. According to HDS, the link you have given informs that ATI doesn't conflict with Rollback Rx, if used for imaging only.

http://support.horizondatasys.com/ic...?questionID=21

3. If I install, ATI after Rollback Rx is installed, then the first and topmost filter in the upper filters become the ATI filter, and not the "Shield.sys" filter.

Thus my question, how does Rollback Rx protect itself and ensures that it is the first and topmost filter in the upper filters, when ATI is installed after the installation of Rollback Rx?

When I look at the upper filters registry the ATI filters is the first and topmost filter in the upper filters, and not "Shield.sys".

Is the above a bug?

OR

It doesn't matter?

Kindest regards,

aladdin.

[aladdin™]

Can Nick10 shed some light on this, or maybe Jacob can get someone to answer the above?

Best regards,

aladdin.

[Froggie]

Great discussion... not sure I can lessen the concern.

UpperFilters - they do all kinds of things in relation to lower level device drivers, but don't necessarily bypass SHIELD, even though SHIELD is above them in the list. Their specific purpose may have nothing to do with the direct access of either disk blocks or the low level Microsloth driver for the disk itself. Once they're executed, they may "re-interface" with a higher level system routine that then calls the lower level drivers.

SHIELD needs to be involved when managing, directly, the allocated (and unallocated) disk space of your HARD DRIVES. If there are other UpperFilter functions above it that never really interface with the disk directly, they present no problem for Rollback. A good example of this is just about any other imaging tool we've played with, regardless of whether it uses one of its own UpperFilters (Acronis), eventually it calls the Microsloth VSS (Volume Shadow Service) to do its active image management for it... and it, in turn, goes through the UpperFilters on its way to the disk and is intercepted by SHIELD to do its Rollback thing. That why all VSS-based imagers fail to get the proper image/MBR when they image the system.

I guess what I'm trying to say is... SHIELD positioning is only important in its relation to other UpperFilters, if those "other" upperfilters" use the same hard disk access method as SHIELD does (probably some sort of DIRECT disk Input/output). To date, when playing around with disk imaging, the only one we've discovered is PHYLOCK (IFW's UpperFilter). Unless we know the internal architecture of each and every UpperFilter installed by every application that uses them, we just don't know for sure.

This is why the general caution... "Keep SHIELD at the top of the list unless you really know how the UpperFilter in question really works." We discovered that PHYLOCK works differently than most every other UpperFilter in question... that's why it needs to be above SHIELD to be successful in its HOT imaging function of a Rollback system.

I really get scared when people talk about special UpperFilters required by ENCRYPTION applications... why, 'cause I really don't know what they're doing at their lowest level. If the last thing they do is call a general Microsloth routine to write the disk, the chances of going through SHIELD are excellent... but we just don't know.

The UpperFilters area, very much like the MBR and Track 0... as far as I'm concerned are very much like that Wild West Show I've mentioned in many of my posts. They're both like WATER RIGHTS here in the states... whoever got there first has the rights to do as they wish with that water, everyone else has to go through them to use those rights correctly.

Wish I could offer more food for thought.

[HDS-Jacob]

I'll see if we can get some additional insight for the above.

Jacob