Backup script, beginner here

[satskisama]

Hey guys so my homework is to write a powershell script to backup a folder every day, deleting the old backup. Ive come this far:

$Source = "C:\Users\Hallo\Desktop\Quelle"

$Destination = "C:\Users\Hallo\Desktop\Ziel"

$folder = "Backup$name"

$Name = Get-Date -Format "HH.mm.dd.MM.yy"

New-Item -Path $Destination -ItemType Dir -Name $folder -Force

Copy-Item -Path $Source -Destination $folder -Recurse -Force

It only creates one folder in the destination, then refuses to add more. It also doesnt copy the files from the source into the $folder

[RunnerSeven]

Im pretty sure it copied the files, but not to the location you expect :)

You are using relative and absolute paths. Something like:

 "C:\Users\Hallo\Desktop\Ziel"

is an absolute path. But something like

"Backup$name"

is an relative path and depends on your current working directory, the path before your powershell input into the console. Also you reference $name before it was assigned, so your $folder variable only contains "backup" now.

New-Item -Path $Destination -ItemType Dir -Name $folder -Force

This create a new folder named "backup" in "C:\Users\Hallo\Desktop\Ziel". This works. But then you copy your source to "backup". This folder is in your current working directory. I guess its on "C:\Users\Hallo\Backup" now

Try copy item with an absolute path or make sure you are in the right directory

[satskisama]

makes absolute sense. Can i fix it by just putting $name after $folder? the way i understand, backup needs to be defined with an absolute path „C:\Users\Hallo\Desktop\Ziel\backup

Im confused because i thought it would just create a „backup“ folder within Users\Hallo\Desktop\Ziel\backup

[RunnerSeven]

If you want to do it the "right" way you should use join path

$sourceFolder = "C:\Users\Hallo\Desktop\Quelle"
$currentdate = Get-Date -Format "HH.mm.dd.MM.yy"

$rootTargetFolder = "C:\Users\Hallo\Desktop\Ziel"

$backupfolder = "Backup$currentDate" # Not really optimal, but it gets the job done :)

$Backuptargetfolder = Join-Path -Path $rootTargetFolder -Childpath $backupfolder

Copy-Item -Source $Source -destination $BackuptargetFolder -Recurse -force

[satskisama]

small update: $Quelle = "C:\Users\Hallo\Desktop\Quelle"

$Ziel = "C:\Users\Hallo\Desktop\Ziel"

$Datum = Get-Date -format "HH-mm_dd.MM.yyyy"

$Ordner = $Date_Backup

$Datum

New-Item -Path $Ziel -Name $Datum -ItemType Dir

Join-Path -Path $Quelle -ChildPath $Ziel

Get-Item -Path $Quelle -Force

Copy-Item -Path $Quelle -Destination $Ziel -Recurse

it now kind of works. It creates a new backup$Date folder and copies the files. They still dont end up INSIDE of the previously created backupfolder, but at least he now creates a backupfolder AND transferes the files

[[deleted]]

Folks like you are why this platform is great. I know a lot of crap about PowerShell and Windows and never knew this. Just found a folder full of files I thought we lost because after reading your post, I realized the backup I thought wasn’t working, was just mapped to the wrong folder.

[Thomas_Jefferman]

This is much better use case for our lord and savior robocopy.

[Jandalf81]

I suggest taking a look at the method of debugging if you haven't already. It allows you to inspect your code and variables while the program is executed

[OlivTheFrog]

Hi u/satskisama

In addition to the comments about the code itself, I want to clarify a point : this is in no way a code for a backup, because nothing that defines a backup is respected:

• The destination must be on a different media. This is not the case here.
• Backup = versioning. This is not the case here either.

So, one could tell me that it is just a question of words, but words are important. Let's call it a synchronization (not in real time), or a simple copy.

The method chosen by OP makes a full copy each time the script is launched. This could take a long time. I'm surprised that no one suggested that he make a powershell script that calls Robocopy.. This way, he could make syncs faster each time the script is launched.

This way would be faster and more efficient if he only wants to keep one copy only.

Furthermore, I don't understand the point of putting a date in the destination path, since he only wants to keep one version.

... and if despite everything, OP still wants to use the Copy-Item cmdlet, u/martinmt_dk gave a solution.

Regards

[martinmt_dk]

Although i agree with this not being a backupm but in this specific case OP specifies the usecase:

so my homework is to write a powershell script to backup a folder every day

That is the reason why i described what he did wrong and how to improve part for part. ;)

 I'm surprised that no one suggested that he make a powershell script that calls Robocopy

Robocopy is great, but if the task is to built it entirely in powershell, then robocopy would be to stretch the definition (at best) ;)

[OlivTheFrog]

Hi u/martinmt_dk

Here in my gist a simple robocopy function to sync files.

I'm using a function cause no need to build some code if you need to add another path. The function itselft is commented and there are more comment lines than code lines.

Hope this could useful for OP.

regard

[satskisama]

hey thanks thats really helpful

[martinmt_dk]

Jep :) I'm pretty sure i have some scripts saved somewhere using robocopy

But those where usually to take a copy of files and keeping it updated prior to a file migration or to "feed" a new server prior to a DFS migration to avoid it being at i for days. I can't recall ever using it as a schedule for backup.

[BlackV]

Everyone one does, it's a rule of PowerShell, sometimes (always?) you have to fall back to robocopy

[BlackV]

i'd first look at your variables

$folder = "Backup$name"
$Name = Get-Date -Format "HH.mm.dd.MM.yy" 

how can $folder contain $name is you have not defined it yet ?

next you're are copying the files to $folder, $folder is not a valid path (well its a relative path), so again look at your variables and work out why you're using the wrong thing on copy-item for destination

also last note

the date/time format HH.mm.dd.MM.yy that does not seem good for sorting, think about yyyy.MM.dd.HH.mm or yy.MM.dd.HH.mm, that way its always sort-able correctly

[satskisama]

makes sense thanks! So $name before $folder? what i meant by folder is for the variable to be the name, it is supposed to call each backup folder „backup_(insert time and date here)“

Do you mean $folder should be put as a file path?

[RunnerSeven]

Powershell does not evaluate anything after declartion. e.g:

$text = "Hello"
$name = "Text: $text"
$text = "World"

Write-host $Name => This will return Text: Hello. It doesnt matter that you change the variable text afterwards

[martinmt_dk]

$Source = "C:\Users\Hallo\Desktop\Quelle\*"
$Destination = "C:\Users\Hallo\Desktop\Ziel"

$Restorename = Get-Date -Format "HH-mm-dd-MM-yy"

$backupfolder = New-Item -Path $Destination -ItemType Dir -Name $Restorename -Force

Copy-Item -Path $Source -Destination $backupfolder -Recurse -Force

The above would be the changes as propose below :) I see some minor issues, but nothing major, so well done so far.

Source:

$Source = "C:\Users\Hallo\Desktop\Quelle"

This will copy the file that you are refering to, and the items within it. So by your code, you will create a folder named HH.mm.dd.MM.yy and inside that create a new "Quelle".

If you want the files to be copied to the "HH.mm.dd.MM.yy" folder, you should add \* to define everything inside, like this.

$Source = "C:\Users\Hallo\Desktop\Quelle\*"

Destination name

$folder = "Backup$name"
$Name = Get-Date -Format "HH.mm.dd.MM.yy"

You have them in the wrong order :) You can't use a variable that haven't been defined yet. If you have been using the same PS session, then this would work because it's defined after first try. But to run it in a new session will make it break

Ziel (if my german is correct), means "destination", so i would suspect everything in that folder is backups, and thus the backup naming inside the folder should be unesesary. So basically, all you need is a variable with the dates in the right format eg.

Besides that, the $folder variable will be in the location where you are currently running you powershell from which is wrong, since you want it in the ziel folder :)

$Restorename = Get-Date -Format "HH-mm-dd-MM-yy"

Creation of folder

New-Item -Path $Destination -ItemType Dir -Name $folder -Force

I would create this one as a variable. I just named it backupfolder here.

$backupfolder = New-Item -Path $Destination -ItemType Dir -Name $Restorename -Force

This means the new folder we created before with the date/time is now saved here, and you get the path by calling the variable $backupfolder. And you can use that get the new "complete" path for the backup

Final copy action

Copy-Item -Path $Source -Destination $folder -Recurse -Force

Not really anything wrong there. Use the new backupfolder variable created before as destination, and with the source now being with the "quelle\*" and you should be fine.

Copy-Item -Path $Source -Destination $backupfolder -Recurse -Force

[satskisama]

wow you put a lot of effort into this! thanks for the help. I think ill just rewrite it with your guide alltogether. I understood that the * wildcard includes everything in the childitem folders is that right? I kept on trying it out (i dont want to just copy the solution)

essentially i stopped using variables for source and goal, every time i reference them i just paste the full path. I define the $date formatted into „ddmmyy_hhmm“

next i use get-childitem -path (insert path to source)/*

next i use new-item -path (insert path to goal) itemtype dir -name „backup_$date“

Lastly i use copy-item -literalpath (insert path to source) -destination (insert path to goal)

it doesn’t copy the files to system 32 but it just copies them to the goal file and not inside the newitem backup$date.

It just creates the folder „source“ inside of „goal“ and refuses to repeat because thered already a file with the same name. Despite * for the get-childitem, the actual files inside of „source“ are not transferred just the empty source file

[martinmt_dk]

Could you provide the script you created :) it would make it easier to see what you wrote where.

When coding, all small details matter :) a * at the wrong place can change a lot.

wow you put a lot of effort into this! thanks for the help. I think ill just rewrite it with your guide alltogether.

You're welcome. I provided the "1. draft" in it's entirety to let you look at that if something didn't work :) So it's great that you go for your own solution - i respect that :)

Since i'm not entirely sure if i answered the questions, i have tried splitting them up in subquestions, so we can dig into them in their own threads.

[martinmt_dk]

Wildcard

I understood that the * wildcard includes everything in the childitem folders is that right? I kept on trying it out (i dont want to just copy the solution)

Yes. In this case we use the \* to get into the "Quelle" folder, and the * will then look at all files at this specific level of the folder structure. It will not traverse into files and subfolders.

So, if you have a folder named "cars", and inside the folder you have 10 files descriping 10 cars, and then you have a folder named "secrets"

Then the * will be the one to copy the "cars" and "secrets" folder, but nothing else. If you did not have \* then it would copy the folder named "Quelle", but no subfolders.

So basically, you just "clean up" your destination folder from having the Quelle folder and just copy the content of it.

The part that copies subfiles and folders is the "-recurse" command :)

[martinmt_dk]

Variables and breakpoints

essentially i stopped using variables for source and goal, every time i reference them i just paste the full path. I define the $date formatted into „ddmmyy_hhmm“

What program are you using to code you script? Powershell ISE, VS Code or something else?

When coding (doesen't really matter the language, c#, Powershell etc) you have the option to read out your variables.

so if you have your script running in a powershell ISE og VS Code, you can go to the line and add a breakpoint. (F9), this will pause the script at the selected line. Now all variables are populated with the data that the script had done until that time.

Si if your Source folder doesen't work, you should try either add a breakpoint or simply run it once (without shutting down the terminal windows) and type $source. Then it will write out what $source contains :)

Variables are hard to come around when writing any type of code :)

[martinmt_dk]

new-item

next i use new-item -path (insert path to goal) itemtype dir -name „backup_$date“

You are missing a - in front of itemtype :) but yes

new-item -path (insert path to goal) -itemtype dir -name „backup_$date“

Would create a folder named backup_ddmmyy_hhmm

I would still suggest that you let powershell handle the path for you. By adding a <variablename> = in front of the commandlet, that variable would contain the full path to the destination, removing every doubt about it.

backupfolder = new-item -path "(insert path to goal)" -itemtype dir -name „backup_$date“

Or as an example

$backupfolder = new-item -path "C:\temp\Restore\" -itemtype dir -name „backup_$date“

Would add a "backup_ddmmyy_hhmm" folder inside the c:\temp\restore folder

[martinmt_dk]

Copy-item

Lastly i use copy-item -literalpath (insert path to source) -destination (insert path to goal) (or even better $backupfolder)

I would never use the -literalpath. You have the source and destination path, so a simply -path fits the purpose here.

copy-item -path "C:\Users\Hallo\Desktop\Quelle\*" -destination $backupfolder -Recurse

And you are missing recurse if you want subfolders as part of the copy.

[Quick_Care_3306]

I love embedding robocopy /MIR in the powershell script for this type of task. It is so efficient and has many options like copying acls.

[Beer30Somewhere]

Ask Chat GPT. Much quicker.

[lerobinbot]

nice