Enabling and Disabling Handoff
Riak KV provides a command-line interface for enabling and disabling handoff on the fly, without needing to set your configuration and restart the node. To enable handoff:
riak-admin handoff enable <inbound|outbound|both> <nodename>
You must specify two things when enabling handoff:
- whether you’d like to enable inbound handoff, outbound handoff, or both
- the node to be targeted by the command (or all nodes)
You can select a target node using either the --node
or the -n
flag.
You can select a direction by specifying inbound
, outbound
, or
both
. The following equivalent commands would enable outbound handoff
on the node riak3@100.0.0.1
:
riak-admin handoff enable outbound --node riak3@100.0.0.1
riak-admin handoff enable outbound -n riak3@100.0.0.1
These two equivalent commands would enable inbound handoff on the node
riak5@100.0.0.1
:
riak-admin handoff enable inbound --node riak5@100.0.0.1
riak-admin handoff enable inbound -n riak5@127.0.0.1
Alternatively, you can enable handoff on all nodes at the same time
using either the -a
or --all
flag. This command would enable both
inbound and outbound handoff on all nodes:
riak-admin handoff enable both --all
As for enabling handoff, the riak-admin disable
command requires that
you specify both both a node or nodes to be targeted by the command and
whether you’d like to disable inbound handoff, outbound handoff, or
both. The disable
command works just like enable
. This command
would disable all forms of handoff on all nodes, to give just one
example:
riak-admin handoff disable both --all
Other Command-line Tools
In addition to enabling and disabling handoff, the
riak-admin
interface enables you to
retrieve a summary of handoff-related activity and other information.
summary
The summary
command provides high-level information about active
handoffs in a cluster.
riak-admin handoff summary
This will return a table that will provide the following information about each node in your cluster:
Header | Description |
---|---|
Node |
The name of the node |
Total |
Total number of active transfers throughout the entire cluster |
Ownership |
Total number of ownership exchanges |
Resize |
Total handoffs related to ring resizing operations (This should always be 0, as the Resize Ring feature has been deprecated) |
Hinted |
Total number of hinted handoffs |
Repair |
Total repair-related handoffs. More information can be found here. |
details
This command provides information only about active transfers.
riak-admin handoff details
If no transfers are currently underway, this command will output No
ongoing transfers
. Otherwise, you will something like this:
config
This command displays the values for handoff-specific configurable parameters on each node in the cluster, including:
transfer_limit
handoff.outbound
handoff.inbound
handoff.port
Descriptions of those parameters can be found in the sections above.