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A Simple Backup Solution

As I've mentioned before, I don't spend much money or time maintaining the "Jameson Datacenter" (a.k.a. my home lab). However, that doesn't mean that I treat my infrastructure lightly.

In previous posts, I've covered many of the Group Policy objects that I use to minimize the maintenance effort associated with running more than a dozen servers (mostly virtual). In this post, I'll provide the details on how I backup these servers.

I should preface this by saying this is not meant to be an "enterprise-level" backup solution. Rather it is simply meant to provide a cheap (actually free) and easy solution to the problem of ensuring you can recover from data loss. Note that data loss rarely occurs through some sort of hardware failure or Act of God (as the insurance folks like to put it). Rather the majority of the time someone accidentally overwrites or deletes a file -- or, gasp, a complete folder hierarchy -- and you subsequently need to restore the data from a backup.

For as long as I can remember, Windows Server has included the NTBackup utility. I'm guessing from the name that this has been around since the days of Windows NT 3.1, but honestly I don't believe I even started running Windows NT until version 3.5. Or was it 3.51? I can't remember. Anyway, I certainly haven't been running NTBackup since then.

Here is the simple batch file that I use to perform scheduled backups:

 @echo off

setlocal

set BACKUP_TYPE=normal

if ("%1") NEQ ("") set BACKUP_TYPE=%1

for /f "tokens=2-4 delims=/ " %%i in ('date /t') do set currentDate=%%k-%%i-%%j
for /f "tokens=1-2" %%i in ('time /t') do set currentTime=%%i %%j
set BACKUP_TIMESTAMP=%currentDate%-%currentTime:~0,2%-%currentTime:~3,2%-%currentTime:~6,2%

set BACKUP_FILE=D:\NotBackedUp\Backups\Backup-%BACKUP_TYPE%-%BACKUP_TIMESTAMP%.bkf

:: ----------------------------------------------------------------------------
call :LogMessage "Starting backup..."
call :LogMessage "BACKUP_TYPE: %BACKUP_TYPE%"
call :LogMessage "BACKUP_FILE: %BACKUP_FILE%"

C:\WINDOWS\system32\ntbackup.exe backup C:\BackedUp /n "Backup created %BACKUP_TIMESTAMP%" /m %BACKUP_TYPE% /j "Backup (%BACKUP_TYPE%)" /f "%BACKUP_FILE%"
if %ERRORLEVEL% neq 0 goto Errors

call :LogMessage "Successfully completed backup."

goto :eof

:: ----------------------------------------------------------------------------
::
:LogMessage

REM Strip leading and trailing quotes and then display message with timestamp
set MESSAGE=%1
set MESSAGE=%MESSAGE:~1,-1%

for /f "tokens=2-4 delims=/ " %%i in ('date /t') do set currentDate=%%k-%%i-%%j
for /f "tokens=1-2" %%i in ('time /t') do set currentTime=%%i %%j
echo %currentDate% %currentTime% - %MESSAGE%

goto :eof

:: ----------------------------------------------------------------------------
::
:Errors

echo Warning! One or more errors detected.

If you've seen any of my scripts before, then you'll quickly notice the typical LogMessage "function" that I use to write messages prefixed with a timestamp. For example here's the output from the log for this morning's backup:

 2009-11-09 12:30 AM - Starting backup...
2009-11-09 12:30 AM - BACKUP_TYPE: differential
2009-11-09 12:30 AM - BACKUP_FILE: D:\NotBackedUp\Backups\Backup-differential-2009-11-09-12-30-AM.bkf
2009-11-09 12:31 AM - Successfully completed backup.

I use similar token parsing of the output from the date and time system commands to generate the name of the backup file (e.g. Backup-differential-2009-11-09-12-30-AM.bkf).

Also note that the type of backup (e.g. normal or differential) can be specified as a parameter when running the batch file. This is really powerful for scheduling different types of backups on various schedules.

Here are the scheduled backups on one of my servers (BEAST):

Scheduled Backups on BEAST
Name Schedule
Daily Backup At 12:00 PM every day
Differential Backup At 12:30 AM every day
Full Backup At 1:00 AM every Sun of every week

The Daily Backup task is configured as follows:

  • Run: C:\BackedUp\Backup.cmd daily >> Backup.log
  • Start in: C:\BackedUp
  • Run as: TECHTOOLBOX\svc-backup

Note that I specifically chose the middle of the day to perform daily backups so that I could potentially recover a file that was created in the morning but mistakenly deleted in the afternoon. I suppose I could schedule incremental backups throughout the day, but honestly, I haven't seen the need given my situation.

Also note that the service account that I use for backups (TECHTOOLBOX\svc-backup) is only a member of the Backup Operators group. It is not a member of the Administrators group.

Consequently there's a known issue with running batch files using scheduled tasks due to out-of-the-box security restrictions on cmd.exe:

"Access is denied" error message when you run a batch job on a Windows Server 2003-based computer

https://support.microsoft.com/kb/867466

Lastly, note that I am doing a simple disk-to-disk backup on my servers, so if there's a fire in the Jameson Datacenter (i.e. my basement) and I lose these servers completely then I'm going to be "hurtin' for certain." However should there ever be a fire in my basement (Heaven forbid), I'm going to be worried about a lot more than just restoring my data from backup. Note that I keep copies of the really important stuff (e.g. digital photos and home videos of my family) on DVDs at my parents' house.

I've read that there's a new backup tool in Windows Server 2008, so I suppose one of these days I'll need to get around to upgrading my backup solution ;-)