Ceph POOL_QUOTA_EXCEEDED

What is Ceph POOL_QUOTA_EXCEEDED

Understanding Ceph and Its Purpose

Ceph is an open-source storage platform designed to provide highly scalable object, block, and file-based storage under a unified system. It is widely used for its ability to handle large amounts of data with high availability and reliability. Ceph's architecture is built to ensure data redundancy and fault tolerance, making it a popular choice for cloud storage solutions.

Identifying the Symptom: POOL_QUOTA_EXCEEDED

When working with Ceph, you may encounter the error POOL_QUOTA_EXCEEDED. This error indicates that a specific pool within your Ceph cluster has reached its configured quota limit, preventing any further write operations to that pool. This can disrupt operations that rely on writing data to the affected pool.

What You Observe

Users or applications attempting to write data to the pool will receive errors, and monitoring tools may alert you to the quota being exceeded. This can lead to application failures or degraded performance if not addressed promptly.

Explaining the Issue: POOL_QUOTA_EXCEEDED

The POOL_QUOTA_EXCEEDED error occurs when the amount of data stored in a pool surpasses the limit set by its quota. Ceph pools are logical partitions of storage, and quotas are used to control the maximum amount of data that can be stored in each pool. This is useful for managing resources and ensuring that no single pool consumes all available storage.

Why This Happens

This issue typically arises when the data growth in a pool is not monitored, or when the quota is set too low for the expected data volume. It can also occur if there is a sudden spike in data storage requirements.

Steps to Fix the POOL_QUOTA_EXCEEDED Issue

To resolve the POOL_QUOTA_EXCEEDED error, you can either increase the pool's quota or delete unnecessary data to free up space. Below are the steps to address this issue:

Step 1: Check Current Pool Quota

First, verify the current quota settings for the pool. Use the following command to list the quotas for all pools:

ceph osd pool get-quota <pool_name>

Replace <pool_name> with the name of the pool you are investigating.

Step 2: Increase the Pool Quota

If you determine that the quota is too low, you can increase it using the following command:

ceph osd pool set-quota <pool_name> max_bytes <new_quota_in_bytes>

Adjust <new_quota_in_bytes> to a value that accommodates your storage needs.

Step 3: Free Up Space

If increasing the quota is not feasible, consider deleting unnecessary data from the pool. Identify and remove data that is no longer needed to free up space.

Additional Resources

For more information on managing Ceph pools and quotas, refer to the official Ceph Documentation. You can also explore community discussions and troubleshooting tips on the Ceph Users Forum.