Blogs

Notes on SNMP MIBs OIDs and Grey Whiskers

With as many grey whiskers as I have, you would think I could grok SNMP in my sleep by now. Unfortunately, everytime I have to deal with it I get frustrated, wonder where the hell my notes from last time are, and start cursing. From now on, here are my notes! I’m typically using Zabbix to poll SNMP OIDs and place the MIBs on the Zabbix server or the Zabbix proxy responsible for SNMP in /usr/share/snmp/mibs.

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Testing OpenShift Enterprise V3

So much for testing OpenShift Origin with Vagrant on OS X, because it does not work yet. Let’s evaluate OpenShift Enterprise v3 on RHEL! First go get yourself an eval license. The OpenShift VMs will run RHEL7.1 and ride on top of RHEV. Documentation First off, here are some starting points to get oriented and acquainted with OpenShift. Docs Getting Started Docs Overview Training Download Prerequisites OpenShift Enterprise 3 Architecture Guide - planning, deployment and operation of an Open Source Platform as a Service Load Balancing Videos

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Testing Openshift Origin V3 with Ansible and Vagrant on OS X

The OpenShift Origin project provides Ansible playbooks and roles for installing OpenShift on various infratructure. I’m going to try out the example using Vagrant and VirtualBox on my Mac. I’m not very familiar with Vagrant or OpenShift v3 yet, so I’m just going to think out loud and see how it goes. I’ve also recently started testing OpenShift Enterprise. Some Background OpenShift Origin is an opensource PaaS (platform as a service).

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How To Scale Up Ansible Playbooks and Roles in a Managable Way

Ansible is Awesome! Ansible is a Mess! So you found Ansible, and you were all Woah! Ansible is awesome! Ansibilize all the things! Then you created a git repo and started hacking. Playbooks look in the current directory to find roles, libraries, and inventories, so naturally you put everything in one big git repo, right? You tried to follow the best practices for writing playbooks, you created roles, and maybe you wrote a filter plugin or a custom module for configuring an application unique to your environment.

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Resources for Learning About Docker

Tutorials Docker’s 10min Tutorial Andrew Baker’s Introduction to Docker Red Hat Workhops Docker and Kubernetes Training - Christian Posta Blog Intro Day 1 Day 2 Day 3 Day 4 Books As of April 2015, O’Reilly has at least 3 books on Docker pending publication. The first two are available in pre-release form now. Using Docker My exercises from the book: identidock Docker Cookbook Docker: Up and Running Blogs Docker Blog Docker Weekly Newsletter Rancher Blog posts some great overviews like this one and this one on monitoring ClusterHQ Blog from makers of Flocker container live migration Videos O’Reilly Introduction to Docker

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Split an Ansible Git Repo and Retain the Commit History

Starting with a jumbled git repo of various Ansible roles, playbooks, inventories, group_vars, etc. I want to create a new repo out of a selection of the subdirectories and retain the commit history. I have an ansible-test repo with a tree that looks roughly like this: . ├── adhoc/ │ ├── rolling-reboot.yml │ └── scripts/ ├── README.md └── runtime/ ├── roles/ │ ├── foo-role/ │ └── zimbra/ │ ├── ansible.cfg │ ├── hosts │ ├── tasks/ │ └── .

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Zimbra Exchange Web Services Crashes OS X Mail.app

Zimbra added EWS support in ZCS 8.5. Right around that time OS X 10.10 was released. Cool! Let’s start syncing all our things to our brand new Mail.app, Calendar.app, and Contacts.app over HTTPS! Strangely, this page says that: ZCS 8.5 targeted EWS support ONLY with Outlook for Mac’s. There was no testing or expectation that the native mac apps would work with the EWS configuration type. Really?! I hope that’s not true.

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Tuning ext4 Creation and Mount Options for Zimbra

Zimbra is a email collaboration suite. Its various compontents perform MTA duties, message store, full text indexing. In a large environment, the number of files and I/O operations can really add up. How we ensure the filesystem is ready to support it? Zimbra’s Recommendations Zimbra offers some guidance for tuning the filesystem, with tips like: Mount file systems with the noatime option. It generally is not important to know the last access time of all the files, so the extra write ops are wasteful.

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Using Ansible Filters to Customize the Order Of Hosts in a List

Zimbra is a email / collaboration suite that is typically deployed in a cluster or clusters of dedicated servers which fill roles like LDAP master, LDAP replica, Proxy, MTA, Mailstore, etc. The LDAP servers are used by all the other servers to store configuration and provisioning data. Servers in the cluster understand where to find the LDAP master (read/write) and LDAP replicas (read only) though values defined in /opt/zimbra/conf/localconfig.xml. There are 2 values relevant to LDAP server lists and they have values like this:

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Openshift V2 and Flask with Virtualenv on OS X

Create a flask app for Openshift with a matching local python virtualenv to perform local testing. In this case we’ll use Python 2.7 on Mac OS X 10.9. Overview of the steps Install Homebrew Install Python Development Environment on Mac OS X Install rhc client tools. Install and Configure a Python Flask for OpenShift Installing Homebrew Ready the system for Homebrew First unhide ~/Library folder. Open Finder Press shift-command-H Press command-J Check Show Library Folder Now Setup shell environment Some of these settings are only relevant to later steps, but go ahead and put them all in now.

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