I'm using SLES 12.2 and recently had some trouble with NTP configuration.
The default settings for NTP in YAST were "Synchronize without Daemon" in the Start NTP Daemon section and "Manual" for "Runtime Configuration Policy". I changed those to "Now and on Boot" and "Auto", respectively. This fixed my problem, as expected.
However, I now need to apply this to a couple hundred machines and need to figure out how to do it from the console.
For the first option, I thought the obvious thing is to enable ntpd.service:
$ systemctl enable ntpd.service
But when I do that and open up YAST, it's still saying "Manual". At the same time if ntpd is disabled and I change it in YAST, it sets it to enabled. So apparently YAST enables the service AND does something else.
The second option I'm not sure about. It has manual, auto, and custom as options in YAST. At first I thought this might be related to the specifics in /etc/ntp.conf, but making changes in YAST doesn't change anything there.
There are of course a number of resources online, but they all get into the specifics of how to configure NTP either in the console or in YAST. What I'm looking for is what each setting in YAST does on the file system specifically.
I'm fairly new to SLES, so there might be something obvious I'm missing. Perhaps there's a setting similar to NM_CONTROLLED for network interfaces where I can simply turn off YAST for NTP and just do it the old-fashioned way?
Usually all SuSE system configuration stuff is stored under
/etc/sysconfig
More Info in documentation
(i posted this question on VMware community forums, with no response)
All of my developers use VMware workstation 11 for running their Visual Studio development environments in Windows. I originally created a base VM, and then simply shared it around to all the users, unbeknown to all the issues it would cause with computer name conflicts, joining the domain, etc. Apparently I didn't 'sysprep' it. Someone with some VMware knowledge tried to help me out to set it up, but im still not sure if it is 100% correct.
I am now at a point where I need to make changes/updates to the base VM (new VS, run Windows Updates, etc) and distribute a new one around to all the developers again, and I need some help to make sure I do it properly this time:
I have 2 VM images currently: 1) a ‘base’ one that opens up to this screen http://screencast.com/t/tBO0IUvwtpbY and 2) one that opens up to this screen http://screencast.com/t/DLV71PeNygrk . I’m assuming it is the ‘base’ one that I make the ‘edits’ to?
If I do edit the ‘base’ VM, what option(s) should I choose in that sys prep dialog?
Once I make the necessary updates to the base VM, what do I need to do to 'prepare' it for distribution to my developers (do I need to run sys prep, do I need to make a copy of VM beforehand, etc)?
Currently the VM has 2 HD's: 1) used for the OS and applications (Persistent and non-Independent), and 2) used to store data files (Persistent and Independent) . Is this the best way to set it up and use the VM (and then use 'snapshots' to revert back to previous states), or should the OS disk be set up as 'non-persistent' after the user has set up the VM for first use (i.e. joined the domain, set up VS Workspace, etc) ? Basically we have had a few scenarios recently where the OS and VS have been corrupted and it took the devs a while to fix it, so I want them to have some sort of way to revert back to a known clean working state.
Thank you
In answer to your questions you are on the right track.
the first screen that opens is correct, customise everything you require in the OS then run the OOBE before distribution
Choose OOBE and tick Generalise, then choose shutdown.
Once the VM is shutdown export it and pass it round your developers. they will need to complete the wizard and then join to the domain if required, this will ensure all the sids are different on each server, remember they must still change the Servers name before joining the domain
Snapshots are best, if your dev needs to reboot etc he doesn't want to loose his changes, he then has the option to revert to a snapshot.
Hopefully this has answered your question, let me know if there is anything else you need :)
I am trying to create a way to transfer the debug information of a C++ project to a remote location for testing. In the current development cycle, small changes to the code require the entire binary (100s MB in size and mostly debug info) to be transferred.
Currently my approach to addressing this is by splitting the debugging information from the object files (the size of which without the debugging info is manageable on my connection) using -gsplit-dwarf and then diffing the debug files against a copy of the build currently on the remote box.
The aim is to have a set of patches for the debug files of a project so that new code can be debugged at a remote location. The connection between the remote location and the local machine is slow and so minimization of the size of the patches is paramount but it should also be balanced with the run time of the tool. I have looked into bsdiff and xdelta as potential solutions and have run into a conundrum where xdetla is fast but too large and bsdiff is perfect in terms of size but the run time and memory requirements are a little higher than I would like it to be.
Is there a tool or approach I am missing or am I just going about this the wrong way? Some alternative to bsdiff and xdelta perhaps? I know that a tool like gbdserver won't work in this situation because of some of the requirements we have with the actual debugging. Could some alteration of bsdiff help the performance? And indeed if the approach I'm using is sound, what would be a good way to keep a copy of the build on the remote machine around to diff against.
The simplest way is to use "strip" to copy the debuginfo into a separate ".debug" file, and then use "strip" again to remove the debug info from the executable that you will deploy. The "strip" manual explains how to do this, look for the "--only-keep-debug" option.
After you do this, you can tell gdb about the separate debug info in various ways. The very best way is to use the "build-id" feature. This is what modern Linux distros do. However there are other ways as well. There's a whole section in the gdb manual about separate debug files.
The key point here is that you can start gdb on the stripped executable and it will find the separate debug info automatically. This data can all be local, so you won't need to deploy the debug info.
If you still care about shrinking debug info even when this is done, you can look at the "dwz" tool. This is a DWARF compressor. However this usually only matters if you plan to ship the debug info somewhere -- distros use it to make it easier to download debug info, but ordinary users won't really see the need.
If I already have an image that exists, can I create an image based on the existing one, except I want to make changes to the exisiting one (mainly configurations).
I do this all the time. I actually keep each of my VMs in a separate directory and duplicate the entire directory to make a copy. All references within the VMX file (configuration) are relative to the current directory.
One thing you need to watch out for. The VMX file has a line with the MAC address of the virtual network card:
ethernet0.generatedAddress = "00:0c:29:ff:1f:c7"
You'll need to change that if you want to run both VMs at the same time - I usually just bump the final digit up by 1 (to c8).
I also change the displayName in that file so I can tell the difference between them when they're running.
Yes, you can just copy the image off to external storage. Just find the image file(s) on your drive and do the copy when the image is not running. You can then change the original all you want. Is this what you are after?
What I do is create a base "clean" VM which I then run Sysprep on before cloning. You can run into a few problems when you don't reset the 'unique' elements of a windows installation and you're trying to run them simultaneously.
I'm running ~20 VMs at the moment and if any one gets seriously messed up (they're used for testing) I've got clean base images of Windows 2000, Windows XP, Vista and Server 2003 at the ready so I can be back up and running in 20mins or less.
Depending on what your needs are, you might try the (free) VMWare Converter. It lets you change drive sizes and other image parameters.
As others have said, this is exactly how you implement full backups for your VMs.
When the VM is not running, merely copy the virtual disks into a different location, then restart the VM.
Trying to honor a feature request from our customers, I'd like that my application, when Internet is available, check on our website if a new version is available.
The problem is that I have no idea about what have to be done on the server side.
I can imagine that my application (developped in C++ using Qt) has to send a request (HTTP ?) to the server, but what is going to respond to this request ? In order to go through firewalls, I guess I'll have to use port 80 ? Is this correct ?
Or, for such a feature, do I have to ask our network admin to open a specific port number through which I'll communicate ?
#pilif : thanks for your detailed answer. There is still something which is unclear for me :
like
http://www.example.com/update?version=1.2.4
Then you can return what ever you want, probably also the download-URL of the installer of the new version.
How do I return something ? Will it be a php or asp page (I know nothing about PHP nor ASP, I have to confess) ? How can I decode the ?version=1.2.4 part in order to return something accordingly ?
I would absolutely recommend to just do a plain HTTP request to your website. Everything else is bound to fail.
I'd make a HTTP GET request to a certain page on your site containing the version of the local application.
like
http://www.example.com/update?version=1.2.4
Then you can return what ever you want, probably also the download-URL of the installer of the new version.
Why not just put a static file with the latest version to the server and let the client decide? Because you may want (or need) to have control over the process. Maybe 1.2 won't be compatible with the server in the future, so you want the server to force the update to 1.3, but the update from 1.2.4 to 1.2.6 could be uncritical, so you might want to present the client with an optional update.
Or you want to have a breakdown over the installed base.
Or whatever. Usually, I've learned it's best to keep as much intelligence on the server, because the server is what you have ultimate control over.
Speaking here with a bit of experience in the field, here's a small preview of what can (and will - trust me) go wrong:
Your Application will be prevented from making HTTP-Requests by the various Personal Firewall applications out there.
A considerable percentage of users won't have the needed permissions to actually get the update process going.
Even if your users have allowed the old version past their personal firewall, said tool will complain because the .EXE has changed and will recommend the user not to allow the new exe to connect (users usually comply with the wishes of their security tool here).
In managed environments, you'll be shot and hanged (not necessarily in that order) for loading executable content from the web and then actually executing it.
So to keep the damage as low as possible,
fail silently when you can't connect to the update server
before updating, make sure that you have write-permission to the install directory and warn the user if you do not, or just don't update at all.
Provide a way for administrators to turn the auto-update off.
It's no fun to do what you are about to do - especially when you deal with non technically inclined users as I had to numerous times.
Pilif answer was good, and I have lots of experience with this too, but I'd like to add something more:
Remember that if you start yourapp.exe, then the "updater" will try to overwrite yourapp.exe with the newest version. Depending upon your operating system and programming environment (you've mentioned C++/QT, I have no experience with those), you will not be able to overwrite yourapp.exe because it will be in use.
What I have done is create a launcher. I have a MyAppLauncher.exe that uses a config file (xml, very simple) to launch the "real exe". Should a new version exist, the Launcher can update the "real exe" because it's not in use, and then relaunch the new version.
Just keep that in mind and you'll be safe.
Martin,
you are absolutely right of course. But I would deliver the launcher with the installer. Or just download the installer, launch it and quit myself as soon as possible. The reason is bugs in the launcher. You would never, ever, want to be dependent on a component you cannot update (or forget to include in the initial drop).
So the payload I distribute with the updating process of my application is just the standard installer, but devoid of any significant UI. Once the client has checked that the installer has a chance of running successfully and once it has downloaded the updater, it runs that and quits itself.
The updater than runs, installs its payload into the original installation directory and restarts the (hopefully updated) application.
Still: The process is hairy and you better think twice before implementing an Auto Update functionality on the Windows Platform when your application has a wide focus of usage.
in php, the thing is easy:
<?php
if (version_compare($_GET['version'], "1.4.0") < 0){
echo "http://www.example.com/update.exe";
}else{
echo "no update";
}
?>
if course you could extend this so the currently available version isn't hard-coded inside the script, but this is just about illustrating the point.
In your application you would have this pseudo code:
result = makeHTTPRequest("http://www.example.com/update?version=" + getExeVersion());
if result != "no update" then
updater = downloadUpdater(result);
ShellExecute(updater);
ExitApplication;
end;
Feel free to extend the "protocol" by specifying something the PHP script could return to tell the client whether it's an important, mandatory update or not.
Or you can add some text to display to the user - maybe containing some information about what's changed.
Your possibilities are quite limitless.
My Qt app just uses QHttp to read tiny XML file off my website that contains the latest version number. If this is greater than the current version number it gives the option to go to the download page. Very simple. Works fine.
I would agree with #Martin and #Pilif's answer, but add;
Consider allowing your end-users to decide if they want to actually install the update there and then, or delay the installation of the update until they've finished using the program.
I don't know the purpose/function of your app but many applications are launched when the user needs to do something specific there and then - nothing more annoying than launching an app and then being told it's found a new version, and you having to wait for it to download, shut down the app and relaunch itself. If your program has other resources that might be updated (reference files, databases etc) the problem gets worse.
We had an EPOS system running in about 400 shops, and initially we thought it would be great to have the program spot updates and download them (using a file containing a version number very similar to the suggestions you have above)... great idea. Until all of the shops started up their systems at around the same time (8:45-8:50am), and our server was hit serving a 20+Mb download to 400 remote servers, which would then update the local software and cause a restart. Chaos - with nobody able to trade for about 10 minutes.
Needless to say that this caused us to subsequently turn off the 'check for updates' feature and redesign it to allow the shops to 'delay' the update until later in the day. :-)
EDIT: And if anyone from ADOBE is reading - for god's sake why does the damn acrobat reader insist on trying to download updates and crap when I just want to fire-it-up to read a document? Isn't it slow enough at starting, and bloated enough, as it is, without wasting a further 20-30 seconds of my life looking for updates every time I want to read a PDF?
DONT THEY USE THEIR OWN SOFTWARE??!!! :-)
On the server you could just have a simple file "latestversion.txt" which contains the version number (and maybe download URL) of the latest version. The client then just needs to read this file using a simple HTTP request (yes, to port 80) to retrieve http://your.web.site/latestversion.txt, which you can then parse to get the version number. This way you don't need any fancy server code --- you just need to add a simple file to your existing website.
if you keep your files in the update directory on example.com, this PHP script should download them for you given the request previously mentioned. (your update would be yourprogram.1.2.4.exe
$version = $_GET['version'];
$filename = "yourprogram" . $version . ".exe";
$filesize = filesize($filename);
header("Pragma: public");
header("Expires: 0");
header("Cache-Control: post-check=0, pre-check=0");
header("Content-type: application-download");
header('Content-Length: ' . $filesize);
header('Content-Disposition: attachment; filename="' . basename($filename).'"');
header("Content-Transfer-Encoding: binary");
This makes your web browser think it's downloading an application.
The simplest way to make this happen is to fire an HTTP request using a library like libcurl and make it download an ini or xml file which contains the online version and where a new version would be available online.
After parsing the xml file you can determine if a new version is needed and download the new version with libcurl and install it.
Just put an (XML) file on your server with the version number of the latest version, and a URL to the download the new version from. Your application can then request the XML file, look if the version differs from its own, and take action accordingly.
I think that simple XML file on the server would be sufficient for version checking only purposes.
You would need then only an ftp account on your server and build system that is able to send a file via ftp after it has built a new version. That build system could even put installation files/zip on your website directly!
If you want to keep it really basic, simply upload a version.txt to a webserver, that contains an integer version number. Download that check against the latest version.txt you downloaded and then just download the msi or setup package and run it.
More advanced versions would be to use rss, xml or similar. It would be best to use a third-party library to parse the rss and you could include information that is displayed to your user about changes if you wish to do so.
Basically you just need simple download functionality.
Both these solutions will only require you to access port 80 outgoing from the client side. This should normally not require any changes to firewalls or networking (on the client side) and you simply need to have a internet facing web server (web hosting, colocation or your own server - all would work here).
There are a couple of commercial auto-update solutions available. I'll leave the recommendations for those to others answerers, because I only have experience on the .net side with Click-Once and Updater Application Block (the latter is not continued any more).