SYNOPSISswift-ring-builder <builder_file> [ACTION] [parameters]
Manipulate the swift ring. Please contribute a better long description!
The parameter [ACTION] can take one of the following values:
create search add set_weight set_info remove rebalance validate write_ring set_min_part_hours
If action is not specified, then swift-ring-builder will display all the storage devices. Below is a full description of each individual actions. In each individual action, you may specify a <search-value>. In that case, then <search-value> can be of the form:
Any part is optional, but you must include at least one part. Examples:
d74 Matches the device id 74
z1 Matches devices in zone 1
z1-220.127.116.11 Matches devices in zone 1 with the ip 18.104.22.168
22.214.171.124 Matches devices in any zone with the ip 126.96.36.199
z1:5678 Matches devices in zone 1 using port 5678
:5678 Matches devices that use port 5678
/sdb1 Matches devices with the device name sdb1
_shiny Matches devices with shiny in the meta data
_snet: 188.8.131.52 Matches devices with snet: 184.108.40.206 in the meta data
Most specific example: d74z1-220.127.116.11:5678/sdb1_"snet: 18.104.22.168"
Nerd explanation: All items require their single character prefix except the ip, in which case the - is optional unless the device id or zone is also included.
CREATEswift-ring-builder <builder_file> create <part_power> <replicas> <min_part_hours>
Creates <builder_file> with 2^<part_power> partitions and <replicas>. <min_part_hours> is number of hours to restrict moving a partition more than once.
Shows information about the ring and the devices within.
SEARCHswift-ring-builder <builder_file> search <search-value>
Shows information about matching devices.
ADDswift-ring-builder <builder_file> add z<zone>-<ip>:<port>/<device_name>_<meta> <weight>
Adds a device to the ring with the given information. No partitions will be assigned to the new device until after running 'rebalance'. This is so you can make multiple device changes and rebalance them all just once.
SET WEIGHTswift-ring-builder <builder_file> set_weight <search-value> <weight>
Resets the device's weight. No partitions will be reassigned to or from the device until after running 'rebalance'. This is so you can make multiple device changes and rebalance them all just once.
SET INFOswift-ring-builder <builder_file> set_info <search-value> <ip>:<port>/<device_name>_<meta>
Resets the device's information. This information isn't used to assign partitions, so you can use 'write_ring' afterward to rewrite the current ring with the newer device information. Any of the parts are optional in the final <ip>:<port>/<device_name>_<meta> parameter; just give what you want to change. For instance set_info d74 _"snet: 22.214.171.124" would just update the meta data for device id 74.
REMOVEswift-ring-builder <builder_file> remove <search-value>
Removes the device(s) from the ring. This should normally just be used for a device that has failed. For a device you wish to decommission, it's best to set its weight to 0, wait for it to drain all its data, then use this remove command. This will not take effect until after running 'rebalance'. This is so you can make multiple device changes and rebalance them all just once.
REBALANCEswift-ring-builder <builder_file> rebalance
Attempts to rebalance the ring by reassigning partitions that haven't been recently reassigned.
VALIDATEswift-ring-builder <builder_file> validate
Just runs the validation routines on the ring.
WRITE RINGswift-ring-builder <builder_file> write_ring
Just rewrites the distributable ring file. This is done automatically after a successful rebalance, so really this is only useful after one or more set_info calls when no rebalance is needed but you want to send out the new device information.
SET MIN PART HOURSswift-ring-builder <builder_file> set_min_part_hours <hours>
Changes the <min_part_hours> to the given <hours>. This should be set to however long a full replication/update cycle takes. We're working on a way to determine this more easily than scanning logs.