FAQ on PIGSTY

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

How to install Docker ？

Install with the docker.yml playbook, targeting at any node managed by Pigsty.

./docker.yml -l <selector>

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

What is the impact of ETCD failure?

ETCD availability is critical for the PGSQL cluster’s HA, which is guaranteed by using multiple nodes. With a 3-node ETCD cluster, if one node is down, the other two nodes can still function normally; and with a 5-node ETCD cluster, two-node failure can still be tolerated. If more than half of the ETCD nodes are down, the ETCD cluster and its service will be unavailable. Before Patroni 3.0, this could lead to a global PGSQL outage; all primary will be demoted and reject write requests.

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

Which components are included in INFRA

Ansible for automation, deployment, and administration;
Nginx for exposing any WebUI service and serving the yum/apt repo;
Self-Signed CA for SSL/TLS certificates;
Prometheus for monitoring metrics
Grafana for monitoring/visualization
Loki for logging collection
AlertManager for alerts aggregation
Chronyd for NTP time sync on the admin node.
DNSMasq for DNS registration and resolution.
ETCD as DCS for PGSQL HA; (dedicated module)
PostgreSQL on meta nodes as CMDB; (optional)
Docker for stateless applications & tools (optional)

How to restore Prometheus targets

If you accidentally deleted the Prometheus targets dir, you can register monitoring targets to Prometheus again with the:

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

Fail to launch multi-node / multi-driver MinIO cluster.

In Multi-Driver or Multi-Node mode, MinIO will refuse to start if the data dir is not a valid mount point.

Use mounted disks for MinIO data dir rather than some regular directory. You can use the regular directory only in the single node, single drive mode.

How to deploy a multi-node multi-drive MinIO cluster?

Check Create Multi-Node Multi-Driver MinIO Cluster

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

Install mongosh

cat > /etc/yum.repos.d/mongo.repo <<EOF
[mongodb-org-7.0]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/7.0/x86_64/
gpgcheck=0
enabled=1
EOF

yum install -y mongodb-mongosh

# or just install via rpm & links
rpm -ivh https://mirrors.tuna.tsinghua.edu.cn/mongodb/yum/el7/RPMS/mongodb-mongosh-1.9.1.x86_64.rpm

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

How to configure NTP service?

If NTP is not configured, use a public NTP service or sync time with the admin node.

If your nodes already have NTP configured, you can leave it there by setting node_ntp_enabled to false.

Otherwise, if you have Internet access, you can use public NTP services such as pool.ntp.org.

If you don’t have Internet access, at least you can sync time with the admin node with the following:

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

ABORT due to postgres exists

Set pg_clean = true and pg_safeguard = false to force clean postgres data during pgsql.yml

This happens when you run pgsql.yml on a node with postgres running, and pg_clean is set to false.

If pg_clean is true (and the pg_safeguard is false, too), the pgsql.yml playbook will remove the existing pgsql data and re-init it as a new one, which makes this playbook fully idempotent.

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

ABORT due to existing redis instance

use redis_clean = true and redis_safeguard = false to force clean redis data

This happens when you run redis.yml to init a redis instance that is already running, and redis_clean is set to false.

If redis_clean is set to true (and the redis_safeguard is set to false, too), the redis.yml playbook will remove the existing redis instance and re-init it as a new one, which makes the redis.yml playbook fully idempotent.

FAQ

Mon, 01 Jan 0001 00:00:00 +0000

If you have any unlisted questions or suggestions, please create an Issue or ask the community for help.

How to Get the Pigsty Source Package?

Use the following command to install Pigsty with one click: bash -c "$(curl -fsSL https://get.pigsty.cc/install)" -- v2.7.0

This command will automatically download the latest stable version pigsty.tgz and extract it to the ~/pigsty directory. You can also manually download a specific version of the Pigsty source code from the following locations.