show-nodes#
Shows all nodes in the EDB Postgres Distributed cluster and their summary.
Synopsis#
Shows all nodes in the EDB Postgres Distributed cluster and their summary, including name, node id, group, and current/target state.
Node States#
State |
Description |
|---|---|
NONE |
Node state is unset when the worker starts, expected to be set quickly to the current known state. |
CREATED |
bdr.create_node() has been executed, but the node isn't a member of any EDB Postgres Distributed cluster yet. |
JOIN_START |
bdr.join_node_group() begins to join the local node to an existing EDB Postgres Distributed cluster. |
JOINING |
The node join has started and is currently at the initial sync phase, creating the schema and data on the node. |
CATCHUP |
Initial sync phase is complete; now the join is at the last step of retrieving and applying transactions that were performed on the upstream peer node since the join started. |
STANDBY |
Node join has finished, but not yet started to broadcast changes. All joins spend some time in this state, but if defined as a Logical Standby, the node will continue in this state. |
PROMOTE |
Node was a logical standby and we just called bdr.promote_node to move the node state to ACTIVE. These two PROMOTE states have to be coherent to the fact, that only one node can be with a state higher than STANDBY but lower than ACTIVE. |
PROMOTING |
Promotion from logical standby to full BDR node is in progress. |
ACTIVE |
The node is a full BDR node and is currently ACTIVE. This is the most common node status. |
PART_START |
Node was ACTIVE or STANDBY and we just called bdr.part_node to remove the node from the EDB Postgres Distributed cluster. |
PARTING |
Node disconnects from other nodes and plays no further part in consensus or replication. |
PART_CATCHUP |
Non-parting nodes synchronize any missing data from the recently parted node. |
PARTED |
Node parting operation is now complete on all nodes. |
Only one node at a time can be in either of the states PROMOTE or PROMOTING. STANDBY, in the Current State or Target State columns, indicates that the node is or will be in a read-only state.
pgd show-nodes [flags]
Options#
No specific command options. See Global Options for global options.
Examples#
Show all nodes in the cluster with a node down#
In this example, there is a multi-node cluster with a data node down.
$ pgd show-nodes
__OUTPUT__
Node Node ID Group Type Current State Target State Status Seq ID
- --- ------- ----- ---- ------------- ------------ ------ ------
bdr-a1 3136956818 group_a data ACTIVE ACTIVE Up 1
bdr-a2 2133699692 group_a data ACTIVE ACTIVE Unreachable 2
witness-a 3889635963 group_a witness ACTIVE ACTIVE Up 3
Show all nodes in the cluster with different node types#
In this example, there is a multi-node cluster with logical standby, witness and subscriber-only nodes. Note that, unlike logical standby nodes, the subscriber-only nodes are fully joined node to the cluster.
$ pgd show-nodes
__OUTPUT__
Node Node ID Group Type Current State Target State Status Seq ID
- --- ------- ----- ---- ------------- ------------ ------ ------
bdr-a1 3136956818 group_a data ACTIVE ACTIVE Up 6
bdr-a2 2133699692 group_a data ACTIVE ACTIVE Up 3
logical-standby-a1 1140256918 group_a standby STANDBY STANDBY Up 9
witness-a 3889635963 group_a witness ACTIVE ACTIVE Up 7
bdr-b1 2380210996 group_b data ACTIVE ACTIVE Up 1
bdr-b2 2244996162 group_b data ACTIVE ACTIVE Up 2
logical-standby-b1 3541792022 group_b standby STANDBY STANDBY Up 10
witness-b 661050297 group_b witness ACTIVE ACTIVE Up 5
witness-c 1954444188 group_c witness ACTIVE ACTIVE Up 4
subscriber-only-c1 2448841809 group_so subscriber-only ACTIVE ACTIVE Up 8