FAQs

What Can I Do If the Error "cmd init: ssh: setenv failed" Is Reported During Installation?

This error is reported because the sshd service on the target server does not support setting of the LANG environment variable during connection.

You need to perform the following command on the target server to update the sshd configuration file and then restart the sshd service.

sudo echo  "AcceptEnv LANG LC_*" >> /etc/ssh/sshd_config && sudo systemctl restart sshd

Does PTK Support Installation Using a Non-Root User?

Yes. PTK self-installation does not have requirements on the user.

However, during cluster deployment, the SSH user configured in a configuration file for performing deployment is required to be a user who has the sudo permission for experiencing all functions. If the sudo user cannot be provided in security mode, PTK supports self-installation in the common user, such as omm but the omm user needs to be created in advance and PTK cannot set user ulimit which requires the sudo permission. The user needs to configure the sudo permission himself. At the same time, the user cannot install MogHA whose instructions require the sudo permission.

Does a Database Support Installation and Management by a Non-Root SSH User?

Yes.

Since PTK v0.7 or later, PTK support installation by a common user. Before installation, the user needs to be created. If the SSH user is not the system user running a database, the SSH user needs to have the sudo permission.

Configuration method of the sudo permission:

Add the following line to the /etc/sudoers file on the target server:

Make sure that no other rules follow this line. Otherwise, it will be overwritten.

username  ALL=(ALL)  NOPASSWD:ALL

What Can I Do If the Database Initialization Error "undefined symbol: EVP_KDF_ctrl" Is Reported?

The installation package is not matched with the host OS. This error typically occurs in the scenario where a CentOS 7 installation package is installed on a system with the high glibc version.

The solution is to replace the installation package with an openEuler package.

What Can I Do If the Error "can not combine with 'abrt-hook-ccpp'" Is Reported?

You can use the abrt(automatic bug report too) service agent to dump the core file. This may lead to core file loss or database downtime.

What is the abrt service

You can fix this bug by modifying the kernel.core_pattern parameter.

# The value can be customized based on the actual requirement.
sysctl -w kernel.core_pattern=/var/log/coredump/%e.%p.%u.%t.core

Do I Need to Pre-Install Python3?

Yes.

Python 3.6 or Python 3.7 needs to be pre-installed because the psutil (python system and process utilities) dynamic library in the OM package supports only this two versions.

PTK and MogDB themselves do not depend on Python3 but gs_om and gs_guc do. Therefore, Python needs to be pre-installed to make sure that the environment meets the requirement.

Can I Install a Database on an Operating System that Is Not Supported by PTK?

Yes.

PTK itself provides a completed and general installation process. It automatically judges the database installation package to be downloaded based on the customer system by default. However, PTK cannot determine the installation package that is really needed when the operating system or operating system version is not supported by PTK. In this case, you can use the -p parameter in the ptk install command to specify an installation package. In view of the fact that the installation is not tested, it may fail. This is normal.

When you try to choose an installation package to adapt to your system, you can comply with the following rules:

1. Make judgment based on the CPU command set architecture.

   uname -m

   For arm64/aarch64, use the openEuler arm64 installation package.

   For x86_64, perform the following operation make judgment.

2. Make judgment based on the glibc version.

   getconf GNU_LIBC_VERSION

   If the glibc version is 2.17 or earlier than 2.17, use the centos7 x86_64 installation package. Otherwise, use the openEuler x86_64 installation package.

Is gs_om Still Supported After a Database Is Installed Using PTK?

Yes.

The cluster installed using PTK is compatible with gs_om. After the database is installed, gs_om dependent static files generate automatically.

Note: gs_om needs user SSH mutual-trust between nodes. After the database is installed using PTK, user SSH mutual-trust is generally established. If it is not established, you need to manually perform the establishment.

What Should I Do If the Error FATAL: semctl(578486307, 7, SETVAL, 0) failed: Invalid argument Is Reported?

You can check whether the value of RemoveIPC in the /etc/systemd/logind.conf directory is no. If it is, restart the server.

How Can I Query the MogDB Versions Supported by PTK?

You can run the ptk candidate db command to query the MogDB versions supported by PTK.

How Can I Query the Operating Systems Supported by PTK?

You can run the ptk candidate os command to query the operating systems supported by PTK.

Can the CM Component Be Installed?

Yes.

Note: To use CM, at least 3 instances are required.

ptk install supports the --install-cm parameter. When this parameter is specified, and all nodes in a cluster are initialized, cm_ctl can be used to start the cluster (if CM is not installed, use gs_ctl to start the cluster). During the starting, the primary instance needs to be chosen and the primary/standby building process is required. Therefore, the starting time is relatively long.

If the command times out during the PTK starting, you can log in to the database server to check the cluster status. In the starting phase, exit of PTK does not interrupt the execution of cm_ctl.

Should PTK and the Database Be Installed on the Same Server?

No.

PTK is designed as a controller. PTK is able to manage multiple database clusters, therefore it is recommended that PTK is installed on a management server independently and the database is installed on a database-dedicated server in the cluster.

Certainly, PTK supports installation on the same server as the database. This is called local installation.

What Should I Do If the Error fail to new sftp client: EOF Is Reported?

This error means that PTK failed to create a sftp connection to the target machine. You can manually run sftp -vvv USER@HOST on the machine where PTK is installed to see the error message in the debug log.

This problem is usually caused by a non-existent or inaccessible sftp-server file configured by Subsystem sftp in the /etc/ssh/sshd_config file on the target machine.