How to debug Divio Cloud deployment problems#
Start with the debugging checklist. Work through the checklist by selecting the most appropriate answer for each question until you arrive at a probable fault for the symptoms you’re seeing.
There is also a complete decision tree for the debugging process.
Debugging checklist#
Start here: a deployment has not worked as expected#
- Does the environment pane show a “Last deployment failed” error message?
The Control Panel shows a Last deployment failed message#
Open the failed link to see the deployment log. The relevant section will be towards the end, so work backwards from the end. Any error will be clearly stated.
- What does the deployment log contain?
Probable fault: temporary problem#
Please try again. This is a rare and usually temporary problem. You may need to wait a few minutes for the condition to clear.
The deployment log contains no obvious error#
The build process succeeded without errors, creating an image and then releasing containers that passed the all health-checks, but all the same, the site is not working as expected. This should not occur, but can do in certain quite specific circumstances.
Check the environment’s runtime logs.
- Do you see any obvious errors in the runtime logs for the environment’s
web
container?
The runtime log contains no errors#
Either the application is failing to write error logs, or some other problem has occurred. Please contact Divio Support.
The runtime log contains errors#
The probable cause is a programming issue. The runtime logs should help you understand the nature of this problem.
The deployment log contains an error#
The end of the log will generally contain the key error.
- Is the error:
Client application error: unable to connect to the application
#
You will see something like:
Trying to connect to the application (0:00:29.486784 with 29 retries)... connection error.
Endpoint verification failed. The client application is not responding to HTTP requests.
The load-balancer was unable to connect to each of the environment’s newly-launched containers and obtain a positive HTTP response within 20 seconds of making the connection. The environment’s runtime logs will contain more information about the problem. If the logs don’t contain a traceback revealing a programming error, the most likely issue is that the application was too slow to start up.
Could not find a version that matches [...]
#
Python application, indicates that a specified dependency cannot be found - typically because two or more of the components in your system have specified incompatible Python dependencies.
For Aldryn Django applications, see How to identify and resolve a dependency conflict.
npm ERR! [...] ERR! /npm-debug.log
#
Probable fault: A Node error has halted the build.
ReadTimeoutError
#
This may occasionally occur when our deployment infrastructure is under heavy load. In most cases you can simply try again.
The environment does not show a “Last deployment failed” error#
Probable fault: programming error at runtime
Sometimes there is no failed deployment log, but the site fails to start. This is very rare, and is typically caused by a programming error that becomes apparent only at runtime, after basic health-checks have passed.
The error will be shown in the site’s runtime logs, available from the Logs menu in the Control Panel.
Decision tree#
This tree represents the logic of the debugging checklist.