Monthly Archives: May 2014

Ceph erasure code jerasure plugin benchmarks

On a Intel(R) Xeon(R) CPU E5-2630 0 @ 2.30GHz processor (and all SIMD capable Intel processors) the Reed Solomon Vandermonde technique of the jerasure plugin, which is the default in Ceph Firefly, performs better. The chart is for decoding erasure … Continue reading

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Create a partition and make it an OSD

Note: it is similar to Creating a Ceph OSD from a designated disk partition but simpler. In a nutshell, to use the remaining space from /dev/sda and assuming Ceph is already configured in /etc/ceph/ceph.conf it is enough to: $ sgdisk … Continue reading

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enable secondary network interface and ignore the default route

When two network interfaces are associated to an OpenStack instance, the Ubuntu precise guest will only configure the first one. Assuming the second can be configured via DHCP, it can be added with: cat > /etc/network/interfaces.d/eth1.cfg <<EOF auto eth1 iface … Continue reading

Posted in Havana, openstack | Leave a comment

Recovering from a cinder RBD host failure

OpenStack Havana Cinder volumes associated with a RBD Ceph pool are bound to a host. cinder service-list –host bm0014.the.re@rbd-ovh +—————+———————–+——+———+——-+ | Binary | Host | Zone | Status | State | +—————+———————–+——+———+——-+ | cinder-volume | bm0014.the.re@rbd-ovh | ovh | enabled … Continue reading

Posted in Havana, ceph, openstack | 3 Comments

Non profit OpenStack & Ceph cluster distributed over five datacenters

A few non profit organizations (April, FSF France, tetaneutral.net…) and volunteers constantly research how to get compute, storage and bandwidth that are: 100% Free Software Content neutral Low maintenance Reliable Cheap The latest setup, in use since ocbober 2013, is … Continue reading

Posted in Havana, ceph, openstack | 5 Comments

Fixing OpenVSwitch and GRE asymetric performances

OpenStack Havana is configured to use OpenVSwitch 1.10.2 as packaged for Ubuntu precise, with a linux-3.11 kernel.The cluster is connected to a 100Mb/s link. When sending data from an instance to the internet (using iperf), it shows ~90Mb/s. When receiving … Continue reading

Posted in Havana, openstack | 8 Comments

Two minor pitfalls when upgrading Havana stable

When upgrading an OpenStack compute or l3 agent node from 1:2013.2 to 1:2013.2.3 on Ubuntu precise 12.04.4: The nova-compute version 1:2013.2 is expected to fail with /var/log/nova/nova-compute.log IncompatibleObjectVersion: Version 1.9 of Instance is not supported when interfaced with a 1:2013.2.3. … Continue reading

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Reseting an instance {power,vm,task}_state in Havana

Sometime, after an hypervisor crash or nova-compute error, an OpenStack instance can be left in a state that cannot be conveniently fixed with nova reset-state. $ nova list +————————————–+—————-+———+… | ID | Name | Status | +————————————–+—————-+———+… | ca9496e9-0bd2-4734-9cf9-eb4e264628f7 | … Continue reading

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