VDC 365 taking a long time.

[dhayes16]

Hello. So we rolled out VDC 365 for a smaller site with about 8 users via FLEX as a VCSP and 300GB total storage. It took about 24 hours to finish that first seed but solid ever since. We rolled it out for another customer but only selected one individual user as a test with a large mailbox and archive (about 160GB total). It has been about 3 days, and it is still processing that one user. Is this normal? I was thinking this might be a throttling issue at Microsoft, but we have used VBO 8.1 on-prem pointing to Wasabi and I do not recall it taking that long. Somewhat concerned. I can reach out to Veeam support on this, but I am just wondering if this initial seed is normal. We have some VERY large tenants to roll in.
Thanks for any input

[micoolpaul]

Hi,

Yes this is normal. Did you disable EWS throttling as per https://www.veeam.com/kb4198?
Exchange protection is throttled per mailbox from Microsoft. With EWS throttling 'disabled' (read: throttle still exists but maximums increased), Microsoft reference an average throughput of 150MB/mailbox/5 minutes.
If you're only protecting one user, we can't parallelise as this is one mailbox with one throttling quota.
Therefore if you take the 150MB/mailbox/5 minute average, you'd backup 1.8GB per mailbox per hour, or 43.2GB per day. 160GB would take between 3-4 days.
You should know that Microsoft can throttle more in response to demands so consider this the minimum backup duration based on their numbers.

Exchange backup policies respond positively to an increase in the number of mailboxes as we can then massively parallelise.

[dhayes16]

Thanks very much for the reply. All seems to be working well now and thanks for the EWS throttling link.

Much appreciated.