docker: Error response from daemon: invalid bit range [4, 4]

Fooling around with docker, trying to create a overlay network. Copied some settings from net, and when starting container, docker reported an error.

root@infra-front:~# docker network create -d overlay --subnet=192.168.50.0/24 --gateway=192.168.50.1 --ip-range=192.168.50.4/32 test

32bdd738a6b7444d8c9a471e451793acd8793db1739f4f660b9981df018252c1

root@infra-front:~# docker run --rm -ti --net test alpine sh

docker: Error response from daemon: invalid bit range [4, 4].

It seems that my network settings where wrong. For now, I just removed gateway and subnet and things started to work.

Jaspersoft Studio 6.2.2 on Fedora 23: no swt-pi-gtk in java.library.path

When starting Jaspersoft Studio 6.2.2 only thing I got was

Jaspersoft Studio:
GTK+ Version Check
Jaspersoft Studio:
An error has occurred. See the log file
/home/jyrki/projects/jasper/TIBCOJaspersoftStudio-6.2.2.final/configuration/1465956968426.log.

Log file had:

TIBCOJaspersoftStudio-6.2.2.final/configuration/org.eclipse.osgi/264/0/.cp/libswt-pi-gtk-4530.so: libgtk-x11-2.0.so.0: cannot open shared object file: No such file or directory
no swt-pi-gtk in java.library.path
/home/jyrki/.swt/lib/linux/x86/libswt-pi-gtk-4530.so: libgtk-x11-2.0.so.0: cannot open shared object file: No such file or directory
Can't load library: /home/jyrki/.swt/lib/linux/x86/libswt-pi-gtk.so

Problem got fixed after installing gtk2.i686 (32 bit version)

sudo dnf install gtk2.i686

Using ldd (print shared library dependencies) helped to find out what was actually missing, as the error message is somewhat miss leading (Can't load library: /home/jyrki/.swt/lib/linux/x86/libswt-pi-gtk.so)

ldd /home/jyrki/projects/jasper/TIBCOJaspersoftStudio-6.2.2.final/configuration/org.eclipse.osgi/264/0/.cp/libswt-pi-gtk-4530.so
ldd: warning: you do not have execution permission for `/home/jyrki/projects/jasper/TIBCOJaspersoftStudio-6.2.2.final/configuration/org.eclipse.osgi/264/0/.cp/libswt-pi-gtk-4530.so'
linux-gate.so.1 (0xf7741000)
libgtk-x11-2.0.so.0 => not found
libgthread-2.0.so.0 => /lib/libgthread-2.0.so.0 (0xf76af000)
libXtst.so.6 => /lib/libXtst.so.6 (0xf76a8000)
libc.so.6 => /lib/libc.so.6 (0xf74da000)
libpthread.so.0 => /lib/libpthread.so.0 (0xf74bd000)
libglib-2.0.so.0 => /lib/libglib-2.0.so.0 (0xf737b000)
libX11.so.6 => /lib/libX11.so.6 (0xf723a000)
libXext.so.6 => /lib/libXext.so.6 (0xf7226000)
libXi.so.6 => /lib/libXi.so.6 (0xf7214000)
/lib/ld-linux.so.2 (0x5660d000)
libxcb.so.1 => /lib/libxcb.so.1 (0xf71ed000)
libdl.so.2 => /lib/libdl.so.2 (0xf71e8000)
libXau.so.6 => /lib/libXau.so.6 (0xf71e4000)

Using Keycloak APIs: "RESTEASY004655: Unable to invoke request"

Following exception was thrown while executing multiple calls to Keycloak API.

Caused by: javax.ws.rs.ProcessingException: RESTEASY004655: Unable to invoke request
at org.jboss.resteasy.client.jaxrs.engines.ApacheHttpClient4Engine.invoke(ApacheHttpClient4Engine.java:287)
at org.jboss.resteasy.client.jaxrs.internal.ClientInvocation.invoke(ClientInvocation.java:436)
at org.jboss.resteasy.client.jaxrs.internal.proxy.ClientInvoker.invoke(ClientInvoker.java:102)
at org.jboss.resteasy.client.jaxrs.internal.proxy.ClientProxy.invoke(ClientProxy.java:64)
at com.sun.proxy.$Proxy276.findAll(Unknown Source)
at org.keycloak.admin.client.resource.ClientsResource$findAll.call(Unknown Source)
Caused by: java.lang.IllegalStateException: Invalid use of BasicClientConnManager: connection still allocated.
Make sure to release the connection before allocating another one.
at org.apache.http.util.Asserts.check(Asserts.java:34)
at org.apache.http.impl.conn.BasicClientConnectionManager.getConnection(BasicClientConnectionManager.java:160)
at org.apache.http.impl.conn.BasicClientConnectionManager$1.getConnection(BasicClientConnectionManager.java:142)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:423)
at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:863)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:57)
at org.jboss.resteasy.client.jaxrs.engines.ApacheHttpClient4Engine.invoke(ApacheHttpClient4Engine.java:283)

I was calling

keycloak.realm(realm).clients().create(representation) 

and did not read anything from response. Simple fix was

            def response = keycloak.realm(realm).clients().create(representation)
            response.close()

Problem with Kubernetes SkyDNS healtz

I had some problems when trying to get DNS working on Kubernetes. I followed instructions from https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/dns. Everything seemed to be working well, but the pod got restarted after 30 seconds. The log for healthz -container had following entries:

2016/03/19 04:25:25 Client ip 10.0.96.1:50326 requesting /healthz probe servicing cmd sleep 10 && nslookup kubernetes.default.svc.kube.local localhost >/dev/null

2016/03/19 04:25:25 Healthz probe error: Result of last exec: nslookup: can't resolve 'kubernetes.default.svc.kube.local': Name does not resolve, at 2016-03-19 04:25:23.967737423 +0000 UTC, error exit status 1

After trying a lot of things, I found a bug report for Alpine Linux. Basically, the nslookup does not respect the server parameter, if /etc/resolv.conf  has entries. Comment on that issues recommends using dig or drill for querying.

So I made a simple image and pushed it into docker hub, https://hub.docker.com/r/jyrki/arm-kubernetes-healthz-drill/. Nothing fancy, just added drill (https://github.com/jyrkiput/arm-kubernetes-healthz-drill/blob/master/Dockerfile). I used the existing image as base as I wanted to have the exechealtz available.

Then I had to change the healtz command to

drill -q kubernetes.default.svc.kube.local @localhost

Kubernetes 1.2.0 beta-1 not starting on Raspbian 8.0

While trying to start kubernetes v1.2.0 on Raspbian 8.0 I ran into problems. Only k8s-master and k8s-master-proxy containers were started so the system was not getting up properly. Logs for k8s-master were telling following:

7215 kubelet.go:2365] skipping pod synchronization - [Failed to start ContainerManager system validation failed - Following Cgroup subsystem not mounted: [memory]]

Cgroup memory subsystem is not enabled by default. You can enable it by adding

cgroup_enable=memory

into /boot/cmdline. Reboot is needed after this.

You can check if the memory subsystem is enabled by listing /sys/fs/cgroup/ which should the have directory called "memory" among others

blkio  cpu  cpuacct  cpu,cpuacct  cpuset  devices  freezer  memory  net_cls  systemd

 

Reveal.js with backgound image and company logo, all in css theme

I wanted to use reveal.js for my presentations. In our company, we have (as usual) a standard template for presentations. The problem was that the background had two parts: A small triangle in top left corner, and company logo in bottom right corner.

CSS3 supports having multiple backgrounds, so after a little tinkering I came up with following css snippets.

body {
  background-image: url('theme_images/corner.svg'), url('theme_images/sysart.svg');
  background-repeat: no-repeat;
  background-position: top left, bottom right;
  background-size: auto 30%, 20% 20%;
  }

The frontpage was some what different.

html.title body {
  background:url("theme_images/front.svg"), url('theme_images/sysart.svg');
  background-repeat: no-repeat;
  background-position: top left, bottom right;
  background-size: 100% auto, 20% 20%;
}

The whole css can be seen in https://github.com/sysart/reveal.js/blob/sysart-theme/sysart.css#L10

Getting project version from Maven project in Jenkins

Execute system Groovy Script with following script

import hudson.FilePath
import hudson.remoting.VirtualChannel

def pomFile = build.getParent().getWorkspace().child('pom.xml').readToString();
def project = new XmlSlurper().parseText(pomFile);      
def param = new hudson.model.StringParameterValue("MAVEN_VERSION", project.version.toString());
def paramAction = new hudson.model.ParametersAction(param);
build.addAction(paramAction);

Now you can use the "MAVEN_VERSION" in build, for example pass it on with "Trigger parameterized build on other projects" post build action by adding predefined parameters:

project_version=${MAVEN_VERSION}

Or in some shell commands

build.sh ${MAVEN_VERSION}

I've found this to be useful when one project deploys artefacts into repository, and another project wants to use those artefacts with exact version number.