backing up windows 7 while running ?

[hhhd1]

Which is better and why ?

Doing a backup of the system partition while the computer is running or restart the computer and boot from a cd/usb.

Doing a backup while the computer is running appears to be allot more convenient.

But what is the down side of it ?

 

[Coup27]

I always backup or more accurately image, home computers in a pre-boot environment.

The reasons are there is no chance of Windows crashing during the backup procedure and the software does not have to navigate around the issue of backing up locked files. Many backup packages offer the clone of locked files via some method but it's another layer onto of the backup process.

Ultimately whenever I do firmware updates, BIOS/UEFI updates or system imaging I like to strip out anything which could crash or cause additional layers of complexity. Backing up in pre-boot is just a lot simplier and it's never gone wrong for me yet.

 

[hhhd1]

I always had the same understanding, and always backed up using a preboot environment.

However, since I am often backing up to a 100mbps network (10MB/s throughput) it gets slow, and I was wondering how bad is backing up a system while running.

 

[Mark R]

It's not terrible backing up a system while running. However, it's not optimal, if you have the option to backup after a clean shutdown.

When a system is backed up during operation, the backup system connects to the OS, and listens for writes to the drive. As the backup proceeds, anytime the OS attempts to write to a sector on the source drive, the backup software intercepts the write; that sector is then backed up immediately (out of normal order), before the OS is allowed to overwrite it.

The backup therefore contains an exact snapshot of the drive at the instant that the backup started.

If you restore from that backup, it will be as if the power had gone out at the instant that the backup started. When the OS boots, it will have to do its "unexpected shutdown" clean-up.