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Microsoft Releases PowerShell DSC For Linux
jones_supa writes: Microsoft is announcing that PowerShell Desired State Configuration (DSC) for Linux is available for download in form of RPM and DEB packages. DSC is a new management platform that provides a set of PowerShell extensions that you can use to declaratively specify how you want your software environment to be configured. You can now use the DSC platform to manage the configuration of both Windows and Linux workloads with the PowerShell interface. Microsoft says that bringing DSC to Linux is another step in the company's "broader commitment to common management of heterogeneous assets in your datacenter or the public cloud." Adds reader benjymouse: DSC is in the same space as Chef and Puppet (and others); but unlike those, Microsofts attempts to build a platform/infrastructure based on industry standards like OMI to allow DSC to configure and control both Windows, Linux and other OSes as well as network equipment like switches, etc.
PowerShell is a modern shell.
Benefits: .NET Framework
- Object oriented, so no awkward parsing of strings. Every item is automatically delivered in its own capsule.
- Integration with other Windows subsystems and the
- Comes with a mini IDE called PowerShell ISE for developing scripts
- Excellent documentation with lots of examples (the Get-Help command)
- Intuitive, easy to remember command names
Every time I have used powershell it has been anything but intuitive or easy to remember.
When you cant win, ad hominem.
It is a lot easier to embrace an "open standard" when you developed it yourself, then donated it to a consortium.
http://en.wikipedia.org/wiki/O...
"- Comes with a mini IDE called PowerShell ISE for developing scripts"
No. A shell that has an IDE to aid formulating godforsaken scripts that mere mortals can't even remember. Just no.
I am putting myself to the fullest possible use, which is all I can think that any conscious entity can ever hope to do.
Why the hell did they put the verb first in command names? They're all Get-This or Set-That or Export-Those or Write-These. This makes an alphabetic list of commands useless, because it groups by verb instead of by noun. It's just one long list of Get- commands, for example, that then need to be searched to find the relevant noun. They should have put the noun first.
It sounds like you dont use it often, which is hardly a good reason to knock it. But I can offer a few tips:
1) Remember that just about everything is an object, with one or more attributes and methods. Even strings are objects, and can use methods such as ".equals(System.obj)". Get-Member is your friend for determining what methods and attributes apply:
"This is a string" | get-member
2) All (properly made) commands take the form of [verb]-[noun]:
get-member
set-ADUser
remove-item
get-help
3) When iterating over a group using "foreach" or "where-object", the special variable $_ is used as a placeholder for the current element:
@("arrayIndex1", "arrayIndex2") | foreach { write-host $_ }
@("RedFish", "BlueFish", "BlueBird") | where-object {$_ -like "blue*"}
4) When in doubt, use one of the following:
Get-Help [command]
Get-Command
$variable | get-member
$variable | format-list *
Im of the opinion that it takes all of about 8 hours to learn to do the majority of things you would want to do in powershell (partly because thats about how long it took me). You just have to take some time to sit down and learn it, and then make an effort to use it instead of GUI administration tools. It is far, far superior to old windows command prompt and vbs,
Have you ever seen init scripts? Theyre way more painful to deal with than anything powershell ever is.
The reason they have an IDE for it is because you can use it to do incredibly complex things, like design GUIs that tie in administration elements from Active Directory, SANs, switch configuration, virtual infrastructure configuration and deployment, and computer administration-- all in one language with a common syntax.
Doing something like that would be a nightmare in bash. It sounds like you havent used powershell, which is a pretty good reason not to comment on it.
Powershell is a shell written by programmers who have no understanding of what you want when administering a box. I remember when it surprised me the first time by being clever and inheriting the size of the console and automatically inserting a CR/LF into the lines of the files I was trying to process.... morons. Just because you can do something doesn't mean that you should, yes OO is a powerful construct but it just gets in the way of a simple scripting tool. Powershell is littered with little gems like this that make it absolutely useless. If you find yourself doing too much with a shell script rewrite it in a more powerful programming language like python, it should take you all of 30 minutes.
Im of the opinion that it takes all of about 8 hours to learn to do the majority of things you would want to do in powershell (partly because thats about how long it took me). You just have to take some time to sit down and learn it, and then make an effort to use it instead of GUI administration tools. It is far, far superior to old windows command prompt and vbs,
I think the same can be said about any *nix shell. Having used powershell a few times, it really just feels like a kludged attempt to bring CMD.exe to something closer to bash.... 20 years later. Now the question becomes just because you can use it, does it mean you should? Last I checked, Windows still has a lot of protections from even the simplest modifications. I much prefer being able to see /etc/fstab than working with some nebulous class with functions that barely make sense.
Then there is some stupid security setting I remember always running into whenever I want to use it.
This makes it sound like you havent done really any research or significant work with powershell other than running one-liners when you need to do something that cant be done in GUI (like deal with Exchange certificates). When thats your exposure, yes, it looks clunky, but thats also ignorance speaking.
The command you want to do to get rid of that prompt is (as administrator) "Set-executionpolicy -Scope MachinePolicy -ExecutionPolicy bypass"-- this sets it forever.
Powershell looks "ugly" because it aims for clarity, not brevity. Commands are explicit in what they do, such that anyone even with no powershell experience could look at most powershell scripts and get a pretty good idea of whats happening; consider a common one-liner below:
Get-ADUser -Filter {Surname -eq "Smith"} | Foreach { Add-ADGroupMember -identity "Domain Admins" -member $_ }
The commands are wordy, but they explain exactly what they do, and each of the parameters are self-describing; you dont need to look at something like "tar -xvzf someFile" and say "gosh, what does the z switch do again".
Instead of trying to unreliably and painfully get out the data you want with a chain of cut, sed, awk, tr on a untyped text string etc you can just get what you want from a object.
All Unix shells are text-oriented. PowerShell is unique in that it is object-oriented and represents a big leap and innovation in shells.
What the hell kind of sadist is going to manage their machines from a Linux machine running PowerShell?
"Unsupported configuration" is the first hurdle that I'd foresee, followed by just being plain, unnecessarily painful.
What does powershell has that python or perl does not have?
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
find . -type f -user root -ctime +7 -print0 | xargs -r -0 grep -l "blah" | xargs -r tar cvzf blah.tar.gz
I can do a lot more with old linux tools than powershell have ever had the capability of.
What is it that Powershell can't do?
I hear that it's incompatible with systemd
*Ducks and runs
I'm a minority race. Save your vitriol for white people.
I think the same can be said about any *nix shell
Clearly you've not done much UNIX shell scripting, if you've not been bitten by the issues with having to escape strings multiple times.
I am TheRaven on Soylent News
At this rate, we'll see MS commit stuff to Wine not long before Christmas.
I'll start a collection for all the tormented souls in Hell, as they'll need lots and lots of warm clothing as the ice age dawns upon them.
Question for religious people: where do unrepentant masochists go when they die?
The nix shells I have used are very powerful, but also very, very painful to learn. Learning sed / awk syntax could easily fill 4 of those 8 hours I mentioned; and thats not even getting into how each and every tool has its own unique idea of how to do syntax. What does a -z switch specify? I dont know, probably fire up that man page and dig through it. What about -h? Is that help, or human readable?
it really just feels like a kludged attempt to bring CMD.exe to something closer to bash.
Theyre not even remotely close. They both operate on the idea that data should be passable between consecutive commands via a pipeline, but bash makes no attempt to deal with different types of data nor any good way to determine what data is incoming. Powershell solves this by being object oriented, and letting you easily determine the type of data coming in, export it to XML, and reimport it at a later session if desired.
As an example-- if you have an error in bash, whats the stack trace look like? Do you have a good way of capturing it? In powershell you can reference the $error[0] variable, and pull up any piece of info you might need to troubleshoot, or even just export the whole thing by "$error | export-cliXML -file C:\somefile.xml" if you're running a nightly job; any issues can later be imported into a new session to diagnose.
Now the question becomes just because you can use it, does it mean you should?
Yes. If you deal with IT infrastructure at all, you would be absolutely crazy not to learn it; its explicitly supported (with native commands) by:
* ALL of the major virtual infrastructure providers (VMWare, HyperV, Xen
* All versions of windows
* A great many storage providers (EMC, NetApp, probably others)
* A number of network infrastructure providers
* IIS, and Exchange -- like it or not these are huge players
* And anything else you want to add support for yourself-- I note that Hadoop for example has community support for powershell
By support, I dont mean in the sense that you could use bash to launch SSH to manage these things. I mean in the sense that VMWare allows you to run the following native powershell commands:
Connect-VIServer myVMCluster
Get-VM | Where-object {$_.powerState -eq "PoweredOn"} | foreach { stop-VM $_}
And all of your VMs will be shut off. Trying to do something like that in bash is doable, it just requires screwing around with scripted SSH access to the VMhosts which is painful, for anyone who has done it.
I much prefer being able to see /etc/fstab than working with some nebulous class with functions that barely make sense.
This is a criticism of object-oriented languages, not powershell. You might as well rail against .Net, or Java, or C++.
Does Microsoft think there are not enough vulnerabilities in Linux?
I've used Powershell several times to write more complex scripts that I would normally have installed Perl on a Win64 system to handle but didn't want to in those particular cases. It worked pretty well once I got all the permission issues worked out, and got kind of familiar with the syntax.
It was still extremely painful to use. The bloody verbosity of the platform (it really is a platform - not a language) was the worst part. It seems to have been engineered straight out of the com-sci-professor-that's-never-had-to-build-anything's handbook. There is no compromise for anything, few shortcuts. The functions were not sensible in my opinion, as some other posters have mentioned, they would use terms that simply had more syllables than obvious synonyms that are normally used for such things. An IDE was necessary so you could scroll through the list of available functions to find the one you were looking for as they were generally not that obvious. Once you get used to them, sure, it's not as bad, but it's still like having an ankle hobbled compared to both knees.
I would say it's fantastic compared to your standard batch script. If that's all you've ever known, I seriously pity you.
I would also say it needs to compromise a great deal to be reasonably useful to people building system scripts, especially coming from unix environments where we've had such tools for $AGES, and have always been asking why our Windows brethren would put up with such silly useless systems.
I would say that the above you say would be a nightmare in bash - it would be much more trivial in perl, which is what I commonly use for such things. A quick for loop to rename files? Definitely bash. Holy cow is that a pain in Powershell.
Lastly, I would say: man pages. Sure, MSDN, but not when you don't have network access, or were you cool with installing 1.7gb more files (seriously??) to support it? Space is cheap until you are running out, at which point it's immediately more expensive. It's just a no-brainer.
Overall, I think Microsoft is incredibly late to this game, over-engineered something as is the norm, and is using marketing tactics to heighten its adoption rather than working on its usefulness. If they could drop in better in-line documentation especially at the command-line (GUIs are great when you have plenty of monitor space and are actually using a UI instead of the console, when you really need to be confident in what that switch is about to do to your last snapshot), make a lot of aliases for the functions (not just the objects) they've developed for the various classes available, and make many of the more commonly used functions statically available directly in the shell instead of buried deep down in some class infrastructure, I for one would be tossing all of my Windows Perl installs (sorry ActiveState, but they're really just band-aids!).
You have the syntax memorized, but the problem is that the input flags for 'find' aren't the same as the ones for 'xargs' which in turn don't overlap with the ones for 'grep' or 'tar'. So that's four different sets of input flags you had to master. Congratulations on your skill. If you run into a text manipulation that's really complex, you have to use sed, awk, or Perl.
PowerShell has its warts, but the command flags are more uniform and its own help search is simpler. Complex text manipulation isn't as complex to implement because a.) you're working with objects and b.) you don't have to learn sed, awk, or Perl to get the job done.
I hate Microsoft's practices, their use of patents, and the windows registry among many other things. But it only benefits the open source community if we examine their tools closely and learn from them. Not everything they do is an inferior knock off of Unix practices.
I only see this causing issues.
1) Windows Admins writing power shell scripts to do stuff on linux boxes
a) setting permissions to 777 because they got in the way.
b) why will it not write the file to c:\?
c) A power shell script developed and tested on Windows, then pushed out to all the servers and crashing the Linux boxes.
c) Do you really believe that a Linux admin would allow a windows Admin to run a Power Shell script as root?
2) Linux Admins being asked to manage windows servers because "You know Power Shell" (If they can get the Linux admin to manage the 300 windows servers on top of the existing 500 Linux servers he manages, it saves them headcount and $$$)
Personally I see it going the way all the other Microsoft products have gone when they release a Linux version. It gets adopted by a few windows admins that are forced to work on linux. However the Linux admins and the bulk of Linux systems will never see it or use it. It will eventually get dropped because of the bugs, memory leaks, and issues that are found in it. Those that are never fixed because they concentrate on the Windows version and ignore the Linux version.
Judging from history it is another Embrace, Extend, Extinguish attempt. Microsoft is just pulling from it's old bag of tricks.
The bloody verbosity of the platform (it really is a platform - not a language) was the worst part
A few things-- the language has a large number of shortcuts, like "fl" instead of "format-list" or "?" instead of "where-object" or "%" instead of "foreach". But the verbosity of it is not really a bad thing, as it makes the resulting code at least somewhat self-documenting; its crystal clear what each command will do most of the time.
An IDE was necessary so you could scroll through the list of available functions to find the one you were looking for as they were generally not that obvious
This is what tab-completion or get-member or even "get-help [command] -examples" is for.
A quick for loop to rename files? Definitely bash. Holy cow is that a pain in Powershell.
$date = get-date -format yyyyMMdd
get-childitem -filter *.txt | foreach {rename-item $_.fullname "$date_$($_.name)"}
Really not that painful.
You mention usefulness- the usefulness as you said is that its a platform supported by an incredible number of vendors. Just about every piece of infrastructure I've come across has vendor-provided powershell integration; the ability to take output from a get-VM command and pass it into a storage provisioning command makes a number of tasks incredibly easy.
Lastly, I would say: man pages.
get-help is your friend, and is far superior to man with the -detailed or -examples switches. Not sure where you're getting the "1.7GB", but this page indicates that the size is more like 9KB.
Build a script library based on short mnemonic commands.
Powershell's naming conventions and basic script library is insanely verbose. Man I hate that language. Damned useful, to be sure, and light years better than any Windows automation tools that came before it, but how I long for commands like sed, ls, mv, cp, head, tail, and so forth.
The world's burning. Moped Jesus spotted on I50. Details at 11.
I hate and mistrust Microsoft as much as the next guy, but let me say this:
* Mathematics is powerful because you take two numbers and an operator and as a result you get something that you can re-use in the same fashion
* Unix is powerful because you take text files and an operator and as a result you get something that you can re-use in the same fashion
* Relational DBMSs are powerful because you take two relations and an operator and as a result you get something that you can re-use in the same fashion
* Monad Shell (now called Power Shell) is powerful because you take object streams and an operator and as a result you get something that you can re-use in the same fashion
A Monad really is something where you put (typically) a constant into a function and get out a specialised function (like, you put 5 into your Monad and out comes a function that takes an integer and returns that same thing plus five).
The Unix world has Perl Shell, Python Shell, and something that the Power Shell is a copy of, the Haskell Shell.
https://github.com/chrisdone/h...
http://www.yesodweb.com/blog/2...
Best regards,
Oliver
Can't you have some sort of aliases in PS? A genuine question.
Other organizations have tried and failed to do this sort of thing, simply because they are superimposing their own stuff on top of the stuff that really does the work. So you either have the code complexity of code managing the tooling that is really doing the work, or the code managing the work, doing the work, and some middleware that doesn't add meaningful value, but does add complexity. Having translation layers rarely does nice things for maintenance and stability, regardless of who is doing it and what the platform is.
XML is like violence. If it doesn't solve the problem, use more.
Build a script library based on short mnemonic commands.
That's easy to do with set-alias. It already has built-in aliases for mv, cp, ls, cat, diff, echo, lp, man, ps, pushd, rm, wget and many more. Use get-alias to see the list of them.
For the other commands you listed, I use UnxUtils. It's a lot lighter than cygwin, although the versions are very old.
can be run without a GUI at all
Not true, or else you wouldn't be able to run 'notepad' on the console. Not that this is necessarily a big deal, but the Core editions are not GUI-free, they start cmd in a window. If you ignore the graphics console and use EMS only, the GUI is still running, just not visible to you.
XML is like violence. If it doesn't solve the problem, use more.
Last time I tried Powershell, it had one major drawback that made me stop using it. Binary output (like PNG) from one program cannot be piped to another program without getting corrupted.
Powershell has some really interesting innovations, so I hope people give it a shot and make constructive criticisms so it can be improved.
You can configure alias's quite easily in poweshell and in fact there are numerous alias's built-in for common commands. Out of the box powershell includes a ton of short alias's including "gci" and "ls" as aliases for Get-ChildItem, % is an alias for ForEach-Object, cp is an alias for Copy-Item, etc.
You can get a list of all alias's defined using Get-Alias (or gal). You can also create an alias using Set-Alias (or sal).
Microsoft generally encourages people to use the full command names in scripts for readability and to make them easier to maintain but there is nothing to stop you from using aliases everywhere including in scripts.
Even more fun when you're calling out to the shell from some other language.
WBEM is a decades old open standard implemented by just about every major software and hardware manufacturer out there. It's shipped with just about every OS. The computer you are using right now probably has CIM implementation built in or at least available in the core OS.
The standard is managed by the Distributed Management Task Force which includes most top software firms. Here is the Java JSR-48: WBEM Services Specification and Implementation for example.
What Microsoft is giving the open-source community is a CIMON ( CIM Object Manager ) implementation. This is fully standards based and Microsoft is just donating the code. But as mentioned earlier Ubuntu and most OSes already ship with a lightweight CIMON.
In the Linux world, Powershell is very limited. You may think it's powerful, but it's really very weak. If you know linux well enough, you have complete control over everything including the kernel.
So you claim, but I have yet to hear of anything that can't be done in Powershell. Undoubtedly there will be something, but I think that most of the time when people make this claim it is because they just assume that it is the case. But when asked to back up the statement...
Well, we can see what has happened. Just further vague claims.
Best practices be damned, you're rockstar coder. Who cares if no one else can look at that code and figure out why you created it and where its probably being used?
Because some of the tools-- rm, mv, ls-- use a "take 2 letters from the word, thats the command" convention, while others are completely different (tar, unzip, gunzip, passwd, man). Theres no common convention whereby you could say"I want to do X" and know what the command is off-hand.
To the uninitiated, there is no particular reason to think "mv" would be the move command; you have to already know that.
Nah. In PowerShell:
iwr "http://server/path/to/file.zip" -outf "${env:TEMP}/file.zip"
You can try to make it look more verbose. But expect to be called out on it.
Reading slashdot one-liner: (irm http://rss.slashdot.org/Slashdot/slashdot).rdf.item | fl title,desc*
Some of those binary blobs though can be useful to move such a way. I recently had to merge, name match , rename and update a few thousand files on windows. I had to manually move them to a unique folder for initial seperation but the I typed ls -name :export-csv l..\list.csv
I then was able to use excel to match file names to what I wanted them to be renamed as and the used another csv to do batch renaming of the files in seconds with the csv containing the files to be renamed and their new file names.
That would have been much harder to do in bash.
While powershell is a bit wordy (think AppleScript wordy)and binary blobs can cause other issues it really isn't a bad set of tools. Better than dos cmd.
i thought once I was found, but it was only a dream.
Part of SCCM is the DSC for Windows servers. What this allows is to validate (ie. scan) for changes to the default build for servers, desktops, and provides integrated reporting. While there are many tools to do this, it is free from MS (minus the OS and SQL DB). If adding Linux to this is a possibility, having your compliance and reporting in one tool, which can leave you from having to run tripwire enterprise or the like due to compliance requirements, might be a win.
I am not saying it is the best thing on the planet, but if it does what the theory states, that would be a huge deal to have 1 less tool to manage to provide compliance reports.
"Those who don't understand UNIX are condemned to reinvent it, poorly."
I gave up with the idea of an useful sig...