Simon Krenger

Anyone who has worked with Oracle has encountered the Oracle “hr” schema in one way or another. The Oracle example schema provides a few simple tables with example data to test out some queries or learn SQL.

So when working with MySQL, I like to have the same schema as well. Luckily, Andrei Ciobanu feels the same way and he provides a wonderful adaptation of this sample schema for MySQL on his website: HR Schema for MySQL and Maria DB.

The SQL script for the schema can be found on GitHub: nomemory/hr-schema-mysql (or in my fork: simonkrenger/hr-schema-mysql).

Thank you Andrei!

So in any larger docker installation, be it Kubernetes or OpenShift, you will encounter pods that crash regularly and enter the “CrashLoopBackOff” status.

$ oc get pod --all-namespaces 
NAMESPACE         NAME                       READY     STATUS             RESTARTS   AGE
[..]
my-project-1      helloworld-11-9w3ud        1/1       Running            0          7h
my-project-2      myapp-simon-43-7macd       0/1       CrashLoopBackOff   3774       9h

Note the container that has status “CrashLoopBackOff” and 3774 restarts.

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Some years ago, I wrote some examples for the WMI client on Linux. I still get a lot of queries from people trying to use the WMI client to access Windows hosts and I am often happy to help if there are any problems.

One of the latest problems occurred when trying to access a Windows host over IPv6:

$ wmic -U 'user%password' //FD00:180::0:0:0:0:0 "Select Caption From Win32_OperatingSystem"
[..]
UNKNOWN - The WMI query had problems. The error text from wmic is: [librpc/rpc/dcerpc_util.c:343:dcerpc_parse_binding()] Unknown dcerpc transport 'FD00'
[librpc/rpc/dcerpc_connect.c:337:dcerpc_pipe_connect_ncacn_ip_tcp_recv()] failed NT status (c0000017) in dcerpc_pipe_connect_ncacn_ip_tcp_recv
[librpc/rpc/dcerpc_connect.c:828:dcerpc_pipe_connect_b_recv()] failed NT status (c0000017) in dcerpc_pipe_connect_b_recv
[wmi/wmic.c:196:main()] ERROR: Login to remote object.
NTSTATUS: NT_STATUS_NO_MEMORY - Memory allocation error

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Thanks to a generous donation of a Visual Studio license, I am able to release the newest versions of the Tanuki Java Service Wrapper. In this post, I can provide version 3.5.32 of the Java Service Wrapper for Windows x64.

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Thanks to a generous donation of a Visual Studio license, I am able to release the newest versions of the Tanuki Java Service Wrapper. In this post, I can provide version 3.5.31 of the Java Service Wrapper for Windows x64.

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Thanks to a generous donation of a Visual Studio license, I am able to release the newest versions of the Tanuki Java Service Wrapper. In this post, I can provide version 3.5.30 of the Java Service Wrapper for Windows x64.

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I recently started working with OpenShift and needed to get a list of all pods on the cluster. I quickly glanced at the documentation but could not find what I wanted. My colleagues quickly pointed me in the right direction:

oc get pod --all-namespaces -o wide

Here is the command with some example output of what to expect:

# oc get pod --all-namespaces -o wide
NAMESPACE                                 NAME                                                       READY     STATUS               RESTARTS   AGE       IP               NODE
my-project                                my-pod-43-d9mo6                                            1/1       Running              0          1d        192.168.0.183    node3.krenger.local
yet-another-project                       another-pod-43-7g3r0                                       1/1       Running              0          2d        192.168.0.184    node4.krenger.local
[..]

If you just want to know which pods are on a certain node, use oc adm manage-node:

oc adm manage-node node3.krenger.local --list-pods

After returning from my vacation, I was asked to provide the latest version of the Tanuki Service Wrapper. Unfortunately, I only have a Windows Server 2003 R2 and a Visual Studio 2008 license. This means I cannot provide newer Java Service Wrappers than 3.5.29, because Tanuki added new features only available with Windows Server 2008 SDK and beyond.

Update: Due to a generous donation of a VS2008 license, I will be able to provide newer versions. Thank you very much!

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In another post I explained how to create a full backup using MySQL Enterprise Backup. Of course, the most important part of the backup is not “making the backup” but the restore of said backup! A backup is worthless if you cannot restore it.

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From May 2016 to May 2017, I will be traveling a lot. As a result of that, there will be no new updates during this period on this blog. However, if you want to get in touch with me, you can reach me via e-mail (see “About” page).

I am looking forward to updating this blog again soon.

All the best,
Simon

Update 30. April 2017: I am back and looking forward to more blog posts!