I'm having a strange intermittent issue with an Azure VM and would appreciate help troubleshooting it.
VM details:
- Standard D4ds v4
- 4 vCPUs
- 16 GiB RAM
- Ubuntu 24.04
- Static public IP
- DNS managed through GoDaddy
- Frontend and backend running on the same VM
The VM doesn't completely stop responding.
The behavior is:
- Normally SSH is fast.
- During the incident, SSH still works, but takes around 3–4 seconds to connect.
- Once connected, typing commands has around 1 second of noticeable delay.
- At the same time, the website goes completely down/unreachable for some period.
- The frontend/backend processes don't appear to crash.
- After the issue clears, SSH becomes normal again and the website starts working again.
- I don't intentionally restart the applications when this happens.
Azure's Availability metric also shows several drops around these periods. I've attached the screenshot.
The domain is managed through GoDaddy and points to a static public IP, so the IP isn't supposed to change.
What I'm trying to understand is what could cause this combination:
SSH = extremely slow/laggy
Website = completely unreachable
Applications = still running
Azure Availability = intermittent drops
Could this indicate packet loss/network problems, an Azure NIC/public IP issue, VM resource contention, or something happening at the Ubuntu networking level?
What should I monitor during the next incident to determine exactly where the problem is?
Thanks!
Source: r/AZURE · by /u/Ok_Cat_2052