Jump to content

Backup OS X Server with Retrospect


Recommended Posts

Hi,
we are considering to backup an OS X Server with Retrospect using a Windows machine with a lot of NTFS storage as the Retrospect server.

Does anyone have any experiences to share?

Of course we would use the latest versions of Retrospect, Retrospect 9.5 app for Windows on the Windows machine and Retrospect client 11.5 for Mac on the OS X Server.
Retrospect says OS X Server, including Mavericks, is fully supported but I cannot find any specific information about how the unique needs of OS X Server backups and restorations have been addressed.
Are all the OS X Services supported? Does the Retrospect client stop the running service, backup the relevant database and restart the service? If so, does it save the service state at each backup execution or does it save only daily backups? How about full restorations?
Thanks in advance.

Link to comment
Share on other sites

It does *not* stop/restart services.  It just backs up the files as they are in use/open as they might be.   

 

So, I back up my servers at 2:00 a.m. when I am fairly sure there are no users on the servers writing data to the server.

 

You could probably script your servers so they shutdown services (i.e. serveradmin stop afp) at a specific time and then restart them when you think the server will be done backing up.

Link to comment
Share on other sites

Thank you very much Maser (and sorry for the late reply).

I was hoping that Retrospect had a more robust OS X Server support, now I can see why they don't explain very much in the documentation about their OS X Server backups inner workings.

Alas, as a matter of fact Retrospect has no more specific OS X Server support than 450-bucks-cheaper Carbon Copy Cloner… :(

Link to comment
Share on other sites

I agree with your statement but my point is that those features are in no way OS X Sever specific.

So, what SPECIFIC problems do you have regarding Retrospect and Mac OS X Server?

 

Mac OS X Server is really nothing more than a plain Mac OS X, but with GUI apps for setting up services already available in Mac OS X.

 

You can try Retrospect for free for 45 days.

Link to comment
Share on other sites

  • 1 month later...

So, what SPECIFIC problems do you have regarding Retrospect and Mac OS X Server?

 

Mac OS X Server is really nothing more than a plain Mac OS X, but with GUI apps for setting up services already available in Mac OS X.

 

Sorry Lennart, but a server is a little bit more than a plain Mac OS X with GUI apps for setting up services… and those services are precisely the problem. I could explain it in a long post but someone else has done it in the OS X Server mailing list, so here you can see the original post:

 

http://lists.apple.com/archives/macos-x-server/2014/Sep/msg00006.html

 

For the sake of completion (and in case the original post becomes unavailable) I paste the exact post:

 

 

 

On 22 Sep 2014, at 1:26am, Andrea Govoni <email@hidden> wrote:

 

> We are considering to backup an OS X Server with Retrospect [snip]

> They say that OS X Server, including Mavericks, is fully supported

 

Sorry, but I suspect this won't work correctly if a backup is taken while the server is running. I'm going to go over the reasons which you understand (from your message) but some readers of this list won't.

 

While a service is running it keeps its state -- its configuration and latest data -- in two places: disk and memory. If you backup just the stuff that's on disk, you will miss changes which haven't been written to disk yet: recent changes in configuration, and changes in data. If you take a copy of just what's on disk you might get an old state (which would be okay, though not the best) but you also might get a state half way through changes (which might be inconsistent or scrambled and lead to later problems).

 

When you shut down the server you shut down all the services it's running. When you do that it flushes all the stuff it's keeping internally to disk, because it won't have any memory when its shutdown. It puts everything in a nice neat state suitable for use when it starts up again.

 

When you use Time Machine to back up an OS X Server computer, it sends a signal to each of its services just before they get backup: "Flush your changes to disk as if you're going to quit.". (Or maybe it actually shuts them down as they're being backed up. I don't know.) This is special code written into Time Machine and it was introduced recently, which is why the first two versions of OS X which did Time Machine hosting had an explicit note in that Time Machine was not suitable for backing up a running OS X Server computer.

 

I don't know that the company behind Retrospect hasn't figured out how to do this properly, but I think if they had they'd be boasting about it more clearly. My theory is that their text about backing up servers is about backing up a file server using access to the files its serving. Which is fine and should work well. But isn't anything like backing up a multi-service server by accessing its hard disk. And what worries me is that they were talking about safe backup of OS X Sever when even Time Machine couldn't do it properly.

 

Simon

 

Link to comment
Share on other sites

My only comment about this (w.r.t flushing the changes) would be -- can you schedule your backups at such time when nobody would be on the server (i.e. 3:00 a.m.?)    That's what I do and, as such, I've not had problems (that I am aware of) of backups of "files on disk" not backing up what is "in memory" at any given point in time.

 

That said -- I do not feel that my user base has anything running at 3:00 a.m. such that I'd need to worry about "in memory" services.   YMMV.

Link to comment
Share on other sites

I've not had problems (that I am aware of) of backups of "files on disk" not backing up what is "in memory" at any given point in time.

 

Exactly!

A server can recover from a power outage, where things "in memory" are not "on disk".

So backing up and restoring what is "on disk" should be no different than booting the same server after a power outage.

Link to comment
Share on other sites

A server can recover from a power outage, where things "in memory" are not "on disk".

So backing up and restoring what is "on disk" should be no different than booting the same server after a power outage.

 

Is this the technical level of the discussion? Really?

A server is generally more fragile than client computers, that's why they are housed in specialized structures with environmental monitoring called "data centers".

Heck, servers usually have dual PSU to minimize the risk of power loss!

Sure, a server could (and probably will) recover from a power outage, just like any other computer, but if the databases on it have been corrupted or not is another matter of fact. Or the database could be OK but some data in it could be damaged or missing.

In the end, It's true that "backing up and restoring what is "on disk" should be no different than booting the same server after a power outage" but I'd expect a bit more from a backup software that declares to be OS X Server compatible.

Link to comment
Share on other sites

Is this the technical level of the discussion? Really?

This is just a user-to-user forum.

I am just a user of Retrospect, albeit a long time user.

 

As such I have always been able to perform bare-metal restores of servers using Retrospect. 

 

I have nothing more to say other than sharing my experience.

 

For more technical discussions, I suggest contacting Retrospect directly.

http://www.retrospect.com/en/support/contact

Select "Pre-sales issue".

Link to comment
Share on other sites

Is this the technical level of the discussion? Really?

A server is generally more fragile than client computers, that's why they are housed in specialized structures with environmental monitoring called "data centers".

Heck, servers usually have dual PSU to minimize the risk of power loss!

Sure, a server could (and probably will) recover from a power outage, just like any other computer, but if the databases on it have been corrupted or not is another matter of fact. Or the database could be OK but some data in it could be damaged or missing.

In the end, It's true that "backing up and restoring what is "on disk" should be no different than booting the same server after a power outage" but I'd expect a bit more from a backup software that declares to be OS X Server compatible.

 

If you know a lot about OS X Server -- you also know that's it's like Apple's "Red-Headed Step Child".   They don't ship hardware with dual PSUs any more, etc...   Even a MacPro is not considered a "server" at this point.    You can't even buy a "Mac Mini Server" now as it's own, branded bundle.

 

OSX Server really is just an advanced version of their client software (with more bells and whistles).    

 

I think a valid argument could be made that maybe retrospect should could stop/restart services as part of a backup -- put in a feature request.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...