Monthly Archives: November 2013

Manage a multi-datacenter crush map with the command line

A new datacenter is added to the crush map of a Ceph cluster: # ceph osd crush add-bucket fsf datacenter added bucket fsf type datacenter to crush map # ceph osd crush move fsf root=default moved item id -13 name … Continue reading

Posted in ceph | 2 Comments

Transparently route a public subnet through shorewall

The 3.20.168.160/27 is routed to a firewall running shorewall. Behind the firewall is an OpenStack cluster running a neutron l3 agent and known to the firewall as 192.168.25.221. A parallel zone is defined as follows: diff -r 34984beb770d hosts — … Continue reading

Posted in shorewall | Leave a comment

Mixing Ceph and LVM volumes in OpenStack

Ceph pools are defined to collocate volumes and instances in OpenStack Havana. For volumes that do not need the resilience provided by Ceph, a LVM cinder backend is defined in /etc/cinder/cinder.conf: [lvm] volume_group=cinder-volumes volume_driver=cinder.volume.drivers.lvm.LVMISCSIDriver volume_backend_name=LVM and appended to the list … Continue reading

Posted in Havana, ceph, openstack | Leave a comment

Creating a Ceph OSD from a designated disk partition

When a new Ceph OSD is setup with ceph-disk on a designated disk partition ( say /dev/sdc3 ), it will not be prepared and the sgdisk command must be run manually: # osd_uuid=$(uuidgen) # partition_number=3 # ptype_tobe=89c57f98-2fe5-4dc0-89c1-f3ad0ceff2be # sgdisk –change-name=”${partition_number}:ceph … Continue reading

Posted in ceph | Leave a comment

Display the default Ceph configuration

The ceph-conf command line queries the /etc/ceph/ceph.conf file. # ceph-conf –lookup fsid 571bb920-6d85-44d7-9eca-1bc114d1cd75 The –show-config option can be used to display the config of a running daemon: ceph -n osd.123 –show-config When no name is specified, it will show the … Continue reading

Posted in ceph | Leave a comment

Migrating from ganeti to OpenStack via Ceph

On ganeti, shutdown the instance and activate its disks: z2-8:~# gnt-instance shutdown nerrant Waiting for job 1089813 for nerrant… z2-8:~# gnt-instance activate-disks nerrant z2-8.host.gnt:disk/0:/dev/drbd10 On an OpenStack Havana installation using a Ceph cinder backend, create a volume with the same … Continue reading

Posted in Havana, ceph, ganeti, openstack | Leave a comment

Collocating Ceph volumes and instances in a multi-datacenter setup

OpenStack Havana is installed on machines rented from OVH and Hetzner. An aggregate is created for machines hosted at OVH and another for machines hosted at Hetzner. A Ceph cluster is created with a pool using disks from OVH and … Continue reading

Posted in Havana, ceph, openstack | Leave a comment

Fragmented floating IP pools and multiple AS hack

When an OpenStack Havana cluster is deployed on hardware rented from OVH and Hetzner, IPv4 are rented by the month and are either isolated ( just one IP, not a proper subnet ) or made of a collection of disjoint … Continue reading

Posted in Havana, openstack | 12 Comments