Installing PGD Proxy#
Installing PGD Proxy#
You can use two methods to install and configure PGD Proxy to manage an EDB Postgres Distributed cluster. The recommended way to install and configure PGD Proxy is to use the EDB Trusted Postgres Architect (TPA) utility for cluster deployment and management.
Installing through TPA#
If the PGD cluster is being deployed through TPA, then TPA installs and
configures PGD Proxy automatically as per the recommended architecture.
If you want to install PGD Proxy on any other node in a PGD cluster,
then you need to attach the pgd-proxy role to that instance in the TPA
configuration file. Also set the bdr_child_group parameter before
deploying, as this example shows. See Installing Trusted Postgres Architect (TPA) for more
information.
- Name: proxy-a1
location: a
node: 4
role:
- pgd-proxy
vars:
bdr_child_group: group_a
volumes:
- device_name: /dev/sdf
volume_type: none
Configuration#
PGD Proxy connects to the PGD database for its internal operations, like
getting proxy options and getting write leader details. Therefore, it
needs a list of endpoints/dsn to connect to PGD nodes. PGD Proxy expects
these configurations in a local config file pgd-proxy-config.yml .
Following is a working example of the pgd-proxy-config.yml file:
log-level: debug
cluster:
name: cluster-name
endpoints:
- "host=bdr-a1 port=5432 dbname=bdrdb user=pgdproxy "
- "host=bdr-a3 port=5432 dbname=bdrdb user=pgdproxy "
- "host=bdr-a2 port=5432 dbname=bdrdb user=pgdproxy "
proxy:
name: "proxy-a1"
By default, in the cluster created through TPA, pgd-proxy-config.yml
is located in the /etc/edb/pgd-proxy directory. PGD Proxy searches
for pgd-proxy-config.yml in the following locations. Precedence
order is high to low.
/etc/edb/pgd-proxy(default) 2.$HOME/.edb/pgd-proxy
If you rename the file or move it to another location, specify the new
name and location using the optional -f or --config-file flag
when starting a service. See the sample service file .
You can set the log level for the PGD Proxy service using the top-level
config parameter log-level , as shown in the sample config. The
valid values for log-level are debug , info , warn , and
error .
cluster.endpoints and cluster.proxy.name are mandatory fields in
the config file. PGD Proxy always tries to connect to the first endpoint
in the list. If it fails, it tries the next endpoint, and so on.
PGD Proxy uses endpoints given in the local config file only at proxy
startup. After that, PGD Proxy retrieves the list of actual endpoints
(route_dsn) from the PGD Proxy catalog. Therefore, the node option
route_dsn must be set for each PGD Proxy node. See route_dsn for
more information.
Configuring health check#
PGD Proxy provides HTTP(S) health check APIs . If the health checks are required, you can enable them by adding the following configuration parameters to the pgd-proxy configuration file. By default, it’s disabled.
cluster:
name: cluster-name
endpoints:
- "host=bdr-a1 port=5432 dbname=bdrdb user=pgdproxy "
- "host=bdr-a3 port=5432 dbname=bdrdb user=pgdproxy "
- "host=bdr-a2 port=5432 dbname=bdrdb user=pgdproxy "
proxy:
name: "proxy-a1"
endpoint: "host=proxy-a1 port=6432 dbname=bdrdb user=pgdproxy "
http:
enable: true
host: "0.0.0.0"
port: 8080
secure: false
cert_file: ""
key_file: ""
probes:
timeout: 10s
You can enable the API by adding the config
cluster.proxy.http.enable: true . When enabled, an HTTP server
listens on the default port, 8080 , with a 10-second timeout and
no HTTPS support.
To enable HTTPS, set the config parameter
cluster.proxy.http.secure: true . If it’s set to true , the
cert_file and key_file must also be set.
The cluster.proxy.endpoint is an endpoint used by the proxy to
connect to the current write leader as part of its checks. When
cluster.proxy.http.enable is true , cluster.proxy.endpoint
must also be set. It can be the same as BDR node routing_dsn , where
host is listen_address and port is listen_port proxy options .
If required, you can add connection string parameters in this endpoint,
like sslmode , sslrootcert , user , and so on.
PGD Proxy user#
The database user specified in the endpoint doesn’t need to be a superuser. Typically, in the TPA environment, pgdproxy is an OS user as well as a database user with the bdr_superuser role.
PGD Proxy service#
We recommend running PGD Proxy as a systemd service. The pgd-proxy
service unit file is located at
/etc/systemd/system/pgd-proxy.service by default. Following is the
sample service file created by TPA:
[Unit]
Description=PGD Proxy
[Service]
Type=simple
User=pgdproxy
Group=pgdproxy
Restart=on-failure
RestartSec=1s
ExecStart=/usr/bin/pgd-proxy -f /etc/edb/pgd-proxy/pgd-proxy-config.yml
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=pgd-proxy
[Install]
WantedBy=multi-user.target
Use these commands to manage the pgd-proxy service:
systemctl status pgd-proxy
systemctl stop pgd-proxy
systemctl restart pgd-proxy
Installing manually#
You can manually install PGD Proxy on any Linux machine using .deb
and .rpm packages available from the PGD repository. The package
name is edb-pgd5-proxy . For example:
# for Debian
sudo apt-get install edb-pgd5-proxy