FAQ

Frequently asked questions about Pigsty NODE module

How to configure NTP service?

NTP is critical for production services. If it is not configured, use public NTP services or Chronyd on the admin node as the time source.

If the nodes already have NTP configured, set node_ntp_enabled to false to preserve that configuration.

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

Without Internet access, use the configuration below to synchronize all nodes with the admin node. You can also use another internal NTP service.

node_ntp_servers:                 # NTP servers in /etc/chrony.conf
  - pool cn.pool.ntp.org iburst
  - pool ${admin_ip} iburst       # assume non-admin nodes do not have internet access, at least sync with admin node

How to force sync time on nodes?

Use chronyc to sync time. You must configure the NTP service first.

ansible all -b -a 'chronyc -a makestep'     # sync time

You can replace all with any group or host IP address to limit the execution scope.

Remote nodes are not accessible via SSH?

A target can require an SSH jump host or other settings that prevent direct ssh ip access. Use Ansible connection parameters to specify the required SSH options. For example:

pg-test:
  vars: { pg_cluster: pg-test }
  hosts:
    10.10.10.11: {pg_seq: 1, pg_role: primary, ansible_host: node-1 }
    10.10.10.12: {pg_seq: 2, pg_role: replica, ansible_port: 22223, ansible_user: admin }
    10.10.10.13: {pg_seq: 3, pg_role: offline, ansible_port: 22224 }

Password required for remote node SSH and SUDO?

When performing deployments and changes, the admin user used must have ssh and sudo privileges for all nodes. Passwordless login is not required.

Pass SSH and sudo passwords with the -k|-K parameters when you run playbooks. To run a playbook as another user, use -eansible_user=<another_user>.

However, Pigsty strongly recommends configuring SSH passwordless login with passwordless sudo for the admin user.

How to create a dedicated admin user with an existing admin user?

Use an existing admin user on the node to run this command. It creates the standard admin user specified by node_admin_username.

./node.yml -k -K -e ansible_user=<another_admin> -t node_admin

How to expose services using HAProxy on nodes?

Use haproxy_services to define exposed services. Run node.yml -t haproxy_config,haproxy_reload to update the configuration.

Here’s an example of exposing Silo: Silo Service Access

Why are all my /etc/yum.repos.d/* files gone?

Pigsty builds a local software repository on infra nodes that includes all dependencies. By default, node_repo_modules is local. Regular nodes use the local software repository on Infra nodes.

This design avoids Internet access and enhances installation stability and reliability. Pigsty moves all original repository definition files to /etc/yum.repos.d/backup. Copy them back as needed.

If you want to preserve the original repo definition files during regular node installation, set node_repo_remove to false.

If you want to preserve the original repo definition files during Infra node local repo construction, set repo_remove to false.

Why did my command line prompt change? How to restore it?

The PS1 environment variable defines the Pigsty shell prompt. Pigsty sets it in /etc/profile.d/node.sh.

If you don’t like it and want to modify or restore it, you can remove this file and log in again.

Why did my hostname change?

Pigsty will modify your node hostname in two situations:

nodename value is explicitly defined (default is empty)
The PGSQL module is declared on the node and the node_id_from_pg parameter is enabled (default is true)

If you don’t want the hostname to be modified, you can set nodename_overwrite to false at the global/cluster/instance level (default is true).

For details, see the NODE_ID section.

What compatibility issues exist with Tencent OpenCloudOS?

OpenCloudOS does not provide the softdog kernel module. Remove it from node_kernel_modules. Add this override to the global configuration variables:

node_kernel_modules: [ ip_vs, ip_vs_rr, ip_vs_wrr, ip_vs_sh ]

What common issues exist on Debian systems?

When using Pigsty on Debian/Ubuntu systems, you may encounter the following issues:

Missing locale

If the system reports locale-related errors, you can fix them with the following command:

localedef -i en_US -f UTF-8 en_US.UTF-8

Missing rsync tool

Pigsty relies on rsync for file synchronization. If the system doesn’t have it installed, you can install it with:

apt-get install rsync

FAQ