Understanding azcopy resumption when downloading blob objects from Azure storage

Question

I have a scenario where I need to download millions of blobs from Azure storage. I'm using azcopy.

More blobs are being added constantly to this storage device (@ ~10K/day).

Imagine my download was disrupted. I try again 30 mins later. By then, ~200 more blobs have already been added to the storage. On my command line, I see:

Incomplete operation with same command line detected at the journal directory "/home/myuser/Microsoft/Azure/AzCopy", do you want to resume the operation?

Which of the following 2 scenarios will happen if I enter "Yes"?

1) It will download the remaining blob files, including the 200 new ones that were added

2) It will download the remaining blob files, excluding the new ones.

Please confirm.

Answer 1

It depends on the names of your new blobs. AzCopy records the last listed blob name into its journal file as a checkpoint, and after resuming, it will continue listing the blobs page by page since that checkpoint. If names of your new blobs are before the checkpoint, they won't be included in this downloading transfer job; otherwise, they will be included.