pg_autoctl show state¶
pg_autoctl show state - Prints monitor’s state of nodes in a given formation and group
Synopsis¶
This command outputs the current state of the formation and groups registered to the pg_auto_failover monitor:
usage: pg_autoctl show state [ --pgdata --formation --group ]
--pgdata path to data directory
--monitor pg_auto_failover Monitor Postgres URL
--formation formation to query, defaults to 'default'
--group group to query formation, defaults to all
--local show local data, do not connect to the monitor
--watch display an auto-updating dashboard
--json output data in the JSON format
Options¶
- --pgdata
Location of the Postgres node being managed locally. Defaults to the environment variable
PGDATA
. Use--monitor
to connect to a monitor from anywhere, rather than the monitor URI used by a local Postgres node managed withpg_autoctl
.- --monitor
Postgres URI used to connect to the monitor. Must use the
autoctl_node
username and target thepg_auto_failover
database name. It is possible to show the Postgres URI from the monitor node using the command pg_autoctl show uri.- --formation
List the events recorded for nodes in the given formation. Defaults to
default
.- --group
Limit output to a single group in the formation. Default to including all groups registered in the target formation.
- --local
Print the local state information without connecting to the monitor.
- --watch
Take control of the terminal and display the current state of the system and the last events from the monitor. The display is updated automatically every 500 milliseconds (half a second) and reacts properly to window size change.
Depending on the terminal window size, a different set of columns is visible in the state part of the output. See pg_autoctl watch.
- --json
Output a JSON formatted data instead of a table formatted list.
Environment¶
PGDATA
Postgres directory location. Can be used instead of the
--pgdata
option.
PG_AUTOCTL_MONITOR
Postgres URI to connect to the monitor node, can be used instead of the
--monitor
option.
XDG_CONFIG_HOME
The pg_autoctl command stores its configuration files in the standard place XDG_CONFIG_HOME. See the XDG Base Directory Specification.
XDG_DATA_HOME
The pg_autoctl command stores its internal states files in the standard place XDG_DATA_HOME, which defaults to
~/.local/share
. See the XDG Base Directory Specification.
Description¶
The pg_autoctl show state
output includes the following columns:
Name
Name of the node.
Node
Node information. When the formation has a single group (group zero), then this column only contains the nodeId.
Only Citus formations allow several groups. When using a Citus formation the Node column contains the groupId and the nodeId, separated by a colon, such as
0:1
for the first coordinator node.Host:Port
Hostname and port number used to connect to the node.
TLI: LSN
Timeline identifier (TLI) and Postgres Log Sequence Number (LSN).
The LSN is the current position in the Postgres WAL stream. This is a hexadecimal number. See pg_lsn for more information.
The current timeline is incremented each time a failover happens, or when doing Point In Time Recovery. A node can only reach the secondary state when it is on the same timeline as its primary node.
Connection
This output field contains two bits of information. First, the Postgres connection type that the node provides, either
read-write
orread-only
. Then the mark!
is added when the monitor has failed to connect to this node, and?
when the monitor didn’t connect to the node yet.Reported State
The latest reported FSM state, as reported to the monitor by the pg_autoctl process running on the Postgres node.
Assigned State
The assigned FSM state on the monitor. When the assigned state is not the same as the reported start, then the pg_autoctl process running on the Postgres node might have not retrieved the assigned state yet, or might still be implementing the FSM transition from the current state to the assigned state.
Examples¶
$ pg_autoctl show state
Name | Node | Host:Port | TLI: LSN | Connection | Reported State | Assigned State
------+-------+----------------+----------------+--------------+---------------------+--------------------
node1 | 1 | localhost:5501 | 1: 0/4000678 | read-write | primary | primary
node2 | 2 | localhost:5502 | 1: 0/4000678 | read-only | secondary | secondary
node3 | 3 | localhost:5503 | 1: 0/4000678 | read-only | secondary | secondary
$ pg_autoctl show state --local
Name | Node | Host:Port | TLI: LSN | Connection | Reported State | Assigned State
------+-------+----------------+----------------+--------------+---------------------+--------------------
node1 | 1 | localhost:5501 | 1: 0/4000678 | read-write ? | primary | primary
$ pg_autoctl show state --json
[
{
"health": 1,
"node_id": 1,
"group_id": 0,
"nodehost": "localhost",
"nodename": "node1",
"nodeport": 5501,
"reported_lsn": "0/4000678",
"reported_tli": 1,
"formation_kind": "pgsql",
"candidate_priority": 50,
"replication_quorum": true,
"current_group_state": "primary",
"assigned_group_state": "primary"
},
{
"health": 1,
"node_id": 2,
"group_id": 0,
"nodehost": "localhost",
"nodename": "node2",
"nodeport": 5502,
"reported_lsn": "0/4000678",
"reported_tli": 1,
"formation_kind": "pgsql",
"candidate_priority": 50,
"replication_quorum": true,
"current_group_state": "secondary",
"assigned_group_state": "secondary"
},
{
"health": 1,
"node_id": 3,
"group_id": 0,
"nodehost": "localhost",
"nodename": "node3",
"nodeport": 5503,
"reported_lsn": "0/4000678",
"reported_tli": 1,
"formation_kind": "pgsql",
"candidate_priority": 50,
"replication_quorum": true,
"current_group_state": "secondary",
"assigned_group_state": "secondary"
}
]