UNIX for Dummies Questions & Answers

I'm trying to set up a RELIABLE backup routine using several USB memory sticks on a SCO 6 Server.

Does anybody have any experience of how to do this? I presume I have to mount the memory stick, copy the files to it & then unmount the stick so that another memory stick could be used for the next backup. Or is there an easy routine to set up to do incremental backups to the same memory stick?

I've had a go at doing this but my server seems to 'freeze' for a long time while copying the files - I would have expected this routine to be very quick because it has no 'mechanical access' at all and just relies on the 'electronics'.

Another problem I've had is that if the memory sticks are not mounted and unmounted correctly the copied file structure becomes corrupt with 'phantom' directories of files etc. and access problems to the memory stick - anybody else any experience of this and how to overcome it?

If anybody has written a routine from the # prompt and is willing to share I would gratefully receive!

Thanks in anticipation!

Because something is electronic it should be instantaneous?

USB is a *serial* bus, dialog goes between the USB stick and the computer over the host controller interface and appears to the operating system as a SCSI device.

So

(a) there are a number of layers and translations going on

(b) the protocol is still serial, hence each bit transferred takes a finite time.

Is it USB 1.1 or USB 2.0?

You don't have to use FAT32 with USB sticks.

Hi Porter!

The memory stick is USB2.0 Kingston Memory 2GB.

My theory has it that even with the memory stick having to negioiate the various layers it should still be much quicker than writing to a CD/DVD or a tape drive - I'm just trying to create a quick simple backup routine that could be used by anybody.

Cheers

The memory used in a USB stick is not like RAM in a computer.

What about the type of host-controller on the PC? Is that 1.1 or 2.0?

It is still quicker and easier than burning multiple CDs.

Everyone who has used USB memory sticks know that they are not as fast as HDDs. One thing that instantly comes to my mind about your saying that you want a "reliable" backup scheme with flash devices, is that every flash-based device has a certain lifetime with the number of writes. I don't know exactly how many writes beyond which the device will start failing, but it is still an issue for automated backups especially if they are done frequently, unless you have done enough tests on it to find it out.

I will not consider a backup scheme "reliable" if it encompasses flash-based devices exclusive (i.e. without other media for backup). So I am rather sceptical of the latest gadgets a.k.a. solid state disks which also use this kind of flash technology, especially because they are so pricey (but also with inherent write limitations).

The question only you can answer is, "How important is my data?"

That being said.......YIKES! I would NEVER use a USB thumbdrive as my desired method for backing up ANYthing. USB drives are meant to be used as "convenient" temp storage to transfer data from one reliable storage media to another if no other means is available, ie network, etc. At least get a USB external hard drive as your backup. Also, you may consider using a RAID in your box. I won't go down the slippery slope of backing up the backup and off-site backup, etc.