Synnefo » snf-ganeti » ganeti-local

Redistribute Config

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Current State and shortcomings

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Currently LURedistributeConfig triggers a copy of the updated configuration

file to all master candidates and of the ssconf files to all nodes. There are

other files which are maintained manually but which are important to keep in

sync. These are:

- rapi SSL key certificate file (rapi.pem) (on master candidates)

- rapi user/password file rapi_users (on master candidates)

Furthermore there are some files which are hypervisor specific but we may want

to keep in sync:

- the xen-hvm hypervisor uses one shared file for all vnc passwords, and copies

  the file once, during node add. This design is subject to revision to be able

  to have different passwords for different groups of instances via the use of

  hypervisor parameters, and to allow xen-hvm and kvm to use an equal system to

  provide password-protected vnc sessions. In general, though, it would be

  useful if the vnc password files were copied as well, to avoid unwanted vnc

  password changes on instance failover/migrate.

Optionally the admin may want to also ship files such as the global xend.conf

file, and the network scripts to all nodes.

Proposed changes

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RedistributeConfig will be changed to copy also the rapi files, and to call

every enabled hypervisor asking for a list of additional files to copy. We also

may want to add a global list of files on the cluster object, which will be

propagated as well, or a hook to calculate them. If we implement this feature

there should be a way to specify whether a file must be shipped to all nodes or

just master candidates.

This code will be also shared (via tasklets or by other means, if tasklets are

not ready for 2.1) with the AddNode and SetNodeParams LUs (so that the relevant

files will be automatically shipped to new master candidates as they are set).