Thanks for reaching out.
Firstly, I would suggest you to look into the below article to make sure that the Storage account is integrated with vnet properly.
So you have a working and a non- working storage account, please make sure the settings/configuration are identical on both the storage accounts and with respect to the function app associated with it. Please check if you have the following settings enabled in the function app as well
WEBSITE_CONTENTOVERVNET = 1.
WEBSITE_VNET_ROUTE_ALL = 1.
WEBSITE_DNS_SERVER =168.63.129.16 (applicable when you are using Azure DNS)
Whitelisting the devops agent ip on the storage account may or may not help. However we suggest to make the above changes which is sufficient for the deployment to be successful. Also, please try to enable verbose logging in the devops pipeline to get more descriptive error message. Verbose logging can be enabled by adding the parameter “system.debug” = true in the devops pipeline.
Also before the deployment, please make sure that the function app is able to reach the storage account or not. You can check this by navigating to the functions page in the Function app and see if you are getting "Azure functions runtime is unreachable" error. If you see this error, then it means that the function app is not able to communicate with the Storage account.
I hope this helps!
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