[Short Tip] Fix mount problems in RHV during GlusterFS mounts

When using Red Hat Virtualization or oVirt together with GLusterFS, there might be a strange error during the first creation of a storage domain: Failed to add Storage Domain xyz. One of the rather easy to fix reasons might be a permission problem: an initial Gluster exported file system belongs to the user root. However, … Continue reading [Short Tip] Fix mount problems in RHV during GlusterFS mounts

Impressions of #AnsibleFest London 2016

The #AnsibleFest was taking place today in London, and I was luckily able to attend. This post shares some impressions from the event, together with interesting announcements and stories. Preface The #AnsibleFest London 2016 took place near the O2 Arena and lasted the entire day. The main highlight of the conference was the network automation … Continue reading Impressions of #AnsibleFest London 2016

[Short Tip] Debug Spamassassin within Amavisd

Filtering e-mail for spam and viruses can be done efficiently with Amavisd-New. Besides its own technologies to identify and filter out Spam it can also make use of Spamassassin and its results. However, since Amavisd starts Spamassassin itself, it sometimes is hard to debug when something is not working. For example in a recent case … Continue reading [Short Tip] Debug Spamassassin within Amavisd

[Howto] Solaris 11 on KVM

Recently I had to test a few things on Solaris 11 and wondered how well it works virtualized with KVM. It does – with a few tweaks. Preface Testing various different versions of operating systems is easy these days thanks to virtualization. However, I’m mainly used to Linux variants and hardly ever install any other … Continue reading [Howto] Solaris 11 on KVM

[Howto] Accessing CloudForms updated REST API with Python

CloudForms comes with a REST API which was updated to version 2.0 in CloudForms 3.2. It covers substantially more functions compared to v1.0 and also offers feature parity with the old SOAP interface. This post holds a short introduction to calling the REST API via Python. Introduction Red Hat CloudForms is a Manager to “manage … Continue reading [Howto] Accessing CloudForms updated REST API with Python

[Short Tip] show processes accessing a file: fuser & lsof

Sometimes it’s good to know which processes access certain files, paths or devices. Think of debugging, but also of certain files blocked due to currently running processes. There are two commonly used tools to get information about which process accesses which file: lsof and fuser. The best known tool is arguably lsof – it lists … Continue reading [Short Tip] show processes accessing a file: fuser & lsof

[Short Tip] Use host names for Docker links

Whenever you link Docker containers together, the question comes up how to access services provided by the linked container: the actual IP address of the container is not static and cannot be guessed beforehand. Sure, the IP address can be looked up by the environment variables ($ env), but not all programs can be modfied … Continue reading [Short Tip] Use host names for Docker links