Azure Functions Runtime Is Unreachable Error: Fix

Firewall prevents the Azure Function host from working correctly

4 min. read

Updated onOctober 4, 2023

updated onOctober 4, 2023

Share this article

Improve this guide

Read our disclosure page to find out how can you help Windows Report sustain the editorial teamRead more

Key notes

Azure Functions Runtime is unreachable error occurs when the Functions runtime can’t start. Usually, this happens if you have exceeded the daily execution quota or deleted the storage account.

In this guide, we will help you troubleshoot the causes of the error and resolve the issue. Let’s start!

What causes the Azure functions runtime is unreachable error?

There could be various reasons why functions app runtime error occurs; some of the popular ones are:

How can I fix the Azure functions runtime is unreachable error?

1. Check if the storage account has been deleted

All function apps need a storage account to work, and if the account is deleted, functions won’t operate. To fix this, check these elements:

2. Check if storage account application settings are deleted

If the connection string was overwritten or deleted, you might not find it. This could have happened because you use Azure Resource Manager scripts or deployment slots to set application settings.

These are the actions you need to take:

3. Check if the storage account is accessible

The Azure function application must have access to the storage account to operate. Here are some things you need to do to resolve the issue:

4. Daily execution quota exhausted

5. Check the firewall settings for the function app

A firewall could restrict the function app; check these areas to be certain:

6. Container errors on Linux

If there is a problem with the container, then the function apps running on Linux in a container can show the error. To fix this, follow these steps:

So, these are some things you need to check to fix azure functions; runtime is an unreachable error. If you have any questions or concerns, please feel free to mention them in the comments below. We will be happy to help!

Azure Functions Runtime Is Unreachable Error: Fix#

What causes the Azure functions runtime is unreachable error?#

How can I fix the Azure functions runtime is unreachable error?#

1. Check if the storage account has been deleted#

2. Check if storage account application settings are deleted#

3. Check if the storage account is accessible#

4. Daily execution quota exhausted#

5. Check the firewall settings for the function app#

6. Container errors on Linux#