Author Archives: Loic Dachary

Ceph Jerasure and ISA plugins benchmarks

In Ceph, a pool can be configured to use erasure coding instead of replication to save space. When used with Intel processors, the default Jerasure plugin that computes erasure code can be replaced by the ISA plugin for better write … Continue reading

Posted in ceph, jerasure | Leave a comment

Improving Ceph python scripts tests

The Ceph command line and ceph-disk helper are python scripts for which there are integration tests ( and It would be useful to add unit tests and pep8 checks. It can be done by creating a python module instead … Continue reading

Posted in ceph | Leave a comment

Testing if a jenkins container finished booting

When running Jenkins as a docker container for test purposes, it is necessary to verify the Jenkins master is fully functional before running the first test cases. The http interface can be tested with a call to the API such … Continue reading

Posted in jenkins | Leave a comment

DNS spoofing with RPZ and bind9

When two web services reside on the same LAN, it may be convenient to spoof DNS entries to use the LAN IP instead of the public IP. It can be done using RPZ and bind9. For instance can be … Continue reading

Posted in Uncategorized | Leave a comment

Mirror github pull requests locally

Each GitHub pull request is associated with a reference in the target repository. For instance the commit sent to pull request 3948 is the reference refs/pull/3948/head. If GitHub successfully merges the pull request in the target branch, another reference is … Continue reading

Posted in git, gitlab | Leave a comment

Using a cloud image with kvm

It would be convenient to have a virt-builder oneliner such as $ virt-builder –arch i386 –ssh-inject ~/.ssh/ fedora-21 to get an image suitable to run and login with $ qemu-kvm -m 1024 -net user,hostfwd=tcp::2222-:22 \ -drive file=fedora-21.qcow2 & $ ssh … Continue reading

Posted in Uncategorized | 2 Comments

Ceph make check in a ram disk

When running tests from the Ceph sources, the disk is used intensively and a ram disk can be used to reduce the latency. The kernel must be rebooted to set the ramdisk maximum size to 16GB. For instance on Ubuntu … Continue reading

Posted in ceph | Leave a comment

Upgrade nodejs on Ubuntu 14.04

To run gh a version of nodejs more recent than the one packaged by default on Ubuntu 14.04 is required: $ apt-cache policy nodejs nodejs: Installed: 0.10.25~dfsg2-2ubuntu1 Candidate: 0.10.25~dfsg2-2ubuntu1 Version table: *** 0.10.25~dfsg2-2ubuntu1 0 500 trusty/universe amd64 Packages 100 … Continue reading

Posted in Uncategorized | Leave a comment

Provisionning a teuthology target with a given kernel

When a teuthology target (i.e. machine) is provisioned with teuthology-lock for the purpose of testing Ceph, there is no way to choose the kernel. But it can be installed afterwards using the following: cat > kernel.yaml <<EOF interactive-on-error: true roles: … Continue reading

Posted in ceph | Leave a comment

Ceph OSD uuid conversion to OSD id and vice versa

When handling a Ceph OSD, it is convenient to assign it a symbolic name that can be chosen even before it is created. That’s what the uuid argument for ceph osd create is for. Without a uuid argument, a random … Continue reading

Posted in ceph | Leave a comment