Azure Blob container sftp server - error SftpRead InvalidRange 416

Wesley hi,

first, the 416 error usually means the client asked for a byte range that the server can't serve. with azure sftp, this often happens when the blob's properties aren't playing nice with sftp requests.

check if the blob's 'content length' is set correctly. sometimes it gets messed up during upload. u can verify this in azure portal under the blob's properties. if it's wrong, reupload the file or update the metadata manually.

make sure the sftp client isn't sending weird range headers. some clients (like winscp) get too clever with partial downloads. try forcing a full download in the client settings.

if u're using azure storage explorer, double check the upload method. sometimes it chunks files weirdly. try uploading with 'block blob' type instead of 'page blob'. https://learn.microsoft.com/en-us/azure/storage/blobs/storage-blobs-introduction

other sftp servers hate invalid ranges too.

test with a different sftp client like filezilla. sometimes the client itself is the culprit.

look at the client logs to see what exact range it's requesting. might give u a clue.

if the files are large, check for network timeouts. sftp can get grumpy with slow connections.

also worth checking if the blob's lease status is 'available'. if it's locked, sftp might freak out )) https://learn.microsoft.com/en-us/rest/api/storageservices/lease-blob

hope this helps,

Alex

and "yes" if you would follow me at Q&A - personaly thx.
P.S. If my answer help to you, please Accept my answer

https://ctrlaltdel.blog/

Hi! Here's what's happening: the 416/InvalidRange error in Blob Storage logs means the SFTP client is requesting a byte range that doesn’t exist in the file. This typically happens when a download tries to resume past the end of the file (EOF), for example if the file is 0 bytes or if it changes during the download. Sometimes you’ll see 416s in the logs even when the download completes successfully — that’s because some clients "probe" the EOF, and under the hood, the SFTP-Blob translation ends up logging a 416.

What to do:

If the downloads are completing, you can safely ignore those 416s in the logs — it’s just a side effect of the EOF probe.

• If downloads are failing, try disabling resume/partial downloads in your SFTP client (e.g., in WinSCP: Preferences - Transfer - Endurance - Disable). Also make sure the client is up to date, and avoid known unsupported versions like Paramiko 1.16.0 or SSH.NET 2016.1.0.

Avoid 0-byte files or files that are being overwritten/truncated while they’re being read. Use Storage Explorer or CLI to check that Content-Length > 0 and that it doesn’t change during the download. (0-byte files trigger 416s in several tools.)

• If you’re using scripts: skip reget/resume, always do a clean get.

To see which requests are generating the 416s, run this query in your logs:

StorageBlobLogs 
| where OperationName == "SftpRead" and StatusCode == 416 
| project TimeGenerated, Uri, ObjectKey, RequesterIPAddress, UserAgent

Hi Wesley Stroop ,

Thanks for your question on the Microsoft Q&A portal.

I hope you’re doing great! I wanted to follow up to see if the information provided by Alex Burlachenko and Michele Ariis was useful.

If it helped resolve your issue, please consider accepting the answer and upvoting it worked for you.

Thanks,

Harish.

Hi all,

I spend already a lot of time trying to resolve this.

Today I have put a simple test.txt with test inside , put it on the storage via azure storage explorer (latest version) and then via filezilla ftp client latest version and still I'm getting this error.

Now it is downloading without issue, but still the error.

the file is set as Blok-Blob