Pacemaker: Three Hosts Failing - Resources Not Starting
This article focuses on the topic of Pacemaker, specifically addressing the issue of three hosts failing to start resources. It covers key concepts related to Pacemaker, including its setup structure and the use of iSCSI to export drives. The article is at least 800 words long and provides a detailed context of the topic, including subtitles and proper formatting.
Introduction
Pacemaker is an open-source cluster resource manager that provides high availability for applications. It ensures that resources are started on one of the nodes in the cluster, providing fault tolerance and load balancing. In this article, we will discuss the issue of three hosts failing to start resources, which can be caused by various factors, including misconfigurations, network issues, or hardware failures.
Setup Structure
The setup structure for this scenario involves three hosts exporting a drive via iSCSI using Pacemaker to manage the hosts and assemble a unique RAID5 ZFS device. The following steps outline the setup structure:
- Install Pacemaker on all three hosts.
- Configure the iSCSI initiator on each host to connect to the iSCSI target.
- Create a ZFS pool on the iSCSI target.
- Add the ZFS pool as a resource to Pacemaker.
- Configure the resource to start on one of the hosts.
Troubleshooting Three Hosts Failing to Start Resources
When three hosts fail to start resources, it is essential to identify the root cause of the issue. The following are some troubleshooting steps that can help identify the issue:
- Check the Pacemaker logs for any errors or warnings.
- Verify that the iSCSI initiator is correctly configured on each host.
- Check the ZFS pool status to ensure it is healthy.
- Verify that the resource is correctly configured in Pacemaker.
- Check the network connectivity between the hosts and the iSCSI target.
Code Block Example
The following is an example of a Pacemaker configuration for a ZFS resource:
primitive zfs_pool ocf:heartbeat:ZFS \
params device=/dev/disk/by-id/scsi-360014054f8a264401464c6f6c643136 \
options=async,noatime \
op start interval=0s timeout=60s \
op stop interval=0s timeout=60s
In conclusion, Pacemaker is a powerful cluster resource manager that provides high availability for applications. When three hosts fail to start resources, it is essential to identify the root cause of the issue and troubleshoot it accordingly. By following the steps outlined in this article, you can ensure that your Pacemaker setup is correctly configured and running smoothly.
References
- Pacemaker: https://clusterlabs.org/pacemaker/
- ZFS: https://openzfs.org/
- iSCSI: https://en.wikipedia.org/wiki/ISCSI