Troubleshoot Proxmox / Ceph storage performance

This runbook covers Troubleshoot Proxmox / Ceph storage performance on a Ceph Tentacle cluster.

When to use

• Active production scenario matching the impact (service-affecting)
• The prerequisites are met

Prerequisites

Before starting this runbook, verify each prerequisite has been met. If a prerequisite is not met, resolve it first or escalate.

• A Proxmox VM reports storage latency
• The RBD image shows slow ops
• Ceph reports slow ops

Pre-checks

Collect evidence before taking action. Evidence is the proof the runbook worked.

# Check Proxmox storage status: pvesm status
# Check the RBD image: rbd info
# Check Ceph: ceph -s, ceph health detail
# Check the Proxmox hosts bridge
# Check the Proxmox hosts CPU / memory / disk
# Check the Ceph OSD hosts resources

Procedure

Step 1

Identify the layer: RBD client, network, Ceph cluster, OSD

Step 2

If RBD client: tune krbd / librbd / queue depth

Step 3

If network: verify bonding, MTU, congestion

Step 4

If Ceph cluster: tune recovery, identify slow OSDs

Step 5

Verify: client latency returns to baseline

Verification

After completing the procedure, verify the result:

# The Proxmox VMs latency returns to baseline
# Ceph reports no slow ops
# Cluster is HEALTH_OK

Rollback

If the procedure does not produce the expected verification, roll back:

• If the slow OSD is the cause: replace it
• If the network is the cause: engage the network team
• If recovery is the cause: tune recovery settings

Escalation

If you cannot roll back or the rollback fails, escalate:

• Storage team
• Network team if the network is the cause