I have multiple devices installed with Ubuntu Server. Some of them have a strange problem:
They can access internet using some applications, such as squid, without any problem.
They can ping to internet IP address.
They can use host / dig to query IP by domain name.
They cannot ping to internet by using domain name directly.
They cannot download file through wget / curl using domain name, but can do with IP.
They cannot use apt, stuck at connecting.
All they use a local dnsmasq as their dns.
After a long time dig, I found the problem and here is the fix.
open the file /etc/nsswitch.conf, search the line with “hosts:” and change the setting to “files dns” (without quotes).
While I’m trying to deploy my site from Visual Studio to a Windows Server 2012 R2 instance, I have to dig a lot for troubleshooting about Web Deploy related problems.
Here are some not listed in Microsoft documents:
Visual Studio need both Web Deploy (Web Deployment Agent Service, MsDepSvc) and Web Management Service (WMSVC).
You cannot install Web Management Service separately.
The easy way to install the both is choose “Web Deploy 3.6 for Hosting Servers” Web Platform Installer.
If you selected “Web Deploy 3.6” in another release, without “for Hosting Servers”, Web Management Service will not be installed.
If you leave Web Deploy installed without Web Management Service, you could add it by install “Web Deploy 3.6 for Hosting Servers” but IT WILL NEVER WORK! You have to UNINSTALL existed Web Deploy first and then reinstall the “Web Deploy 3.6 for Hosting Servers”.
Microsoft launched KB3194721 (for SqlServer 2012) and KB3194718 (for SqlServer 2014) this month though WSUS channel. If you choose to deploy them though WSUS, just as I did, you may face a bug on a cluster based SqlServer.
On the server with SqlServer installed as cluster, these patches just act as cancelled or failed. For digging the problem, I download the package from Microsoft Download Site and try to install them manually. The first step is decompressing. Files are placed on the largest drive (I dunno it based on the total or free space). In my case, one disk drive for a database role is chosen. Then the upgrading procedure starts, with a bug that is:
If the owner of this instance role of cluster is the same computer, the role will be automatically stopped during update process, and will be started later. But while the role is set to stop, the disk drive is offline with it. So, if that drive is the largest, sadly, the update procedure fails — source files of update package are missing.
Even you run these packages manually, not from WSUS, it’s still not possible to choose the folder to decompress. If some drive of database role of cluster is larger than all server self-owned disks, you may want to STOP THE NODE in cluster as a workaround.
In our company, our major productive servers are hosted in vSphere as Windows-based virtual machines. Some of them need very big disks. Through the largest disk space supported in vSphere is 16TB (or maybe more, i dunno), I’m not interested to create such a big file in VMFS. It will be really a pain your *** when you have to move such a big file among datastores, even among data facilities by using portable hard drives.
Creating smaller disks instead of a big one for every Windows-based VM, IMHO.
Fortunately, Windows support to merge small disks as a big one, using dynamic disk function. There are 4 kinds of volume can be supported in such a condition: Spanned, Striped, Mirrored and RAID-5. You can consider them like JBOD, RAID-0, RAID-1 and RAID-5 functions in a simple legacy storage device.
Because data protection is existed in the SAN, Mirrored and RAID-5 volumes are not considered at all. Striped will make it a little faster when lots of virtual disks fight for limited IOPS resources within one datastore. But there is no way to extend any stripped volume (https://technet.microsoft.com/en-us/library/cc770938.aspx).
So, the useless volume format in a traditional world, spanned volume, is the best solution, maybe the only one. Next time when you need to create big virtual disks for Windows in any virtualization environment, don’t forget to consider using Spanned Volumes.
I’m testing to add the boot.wim files from Windows 10 1607 (10.0.14393) installation discs to Windows Deployment Services on Windows Server 2012 R2.
Test 1: Add x86 and x64 boot files to WDS
Test 2: Add drivers to boot files.
Failed with WDS client on Windows Server 2012 R2.
Succeeded with WDS client on Windows Server 2016 TP5 connected to the target WDS.
Test 3: Create discover images.
Passed but failed in Test 6.
Test 4: Create x64 capture image.
Test 5: Boot from boot files.
Test 6: Boot from discover images embedded in ISO files.
Failed with error: WdsClient: There was a problem initializing WDS Mode.
Try to use other images created from WDS clients of Windows Server 2016 TP5: failed in the same way.
Test 7: Boot from x64 capture image.
Test 8: Capture an instance of Windows 10.0.14393.
Instance for test: Windows 10.0.14393.10 x86 with up-to-date Office 2016.
Test 9: Deploy an instance of Windows 10.0.14393 through WDS.