Hello,
I have this issue with some of my XOA appliance with the update from 5.53.1 to 5.54.0 with stable version selected.
Which are these old appliances? Which are the new appliances?

I confirm what @nikade say. Even if i use a 10Gb and set the concurrent backup to 10, the speed will be always the same.
If we use proxy XOA or similar idea i think we can speed the backup but not to a point we would like.
We usually make a differential backup, but for us (67 VM = 300 GB transfer and 300 GB merged - diff backup, XOA take from 4 to 6 Hours).

Sorry, i know this isn't a ticket, i meant the question here on the forum.
and we write this thread because we cannot find a solution anywhere for our issue/question to speed up the backup.
We are making a lot of test right now, but we are not going better in anyway and we found a lot of limits in XOA/XCP-ng and Xen server 7.1 CU2 to, we are a bit worried about this issue with the backup.

Hi,
i opened this ticket because our datacenter has 67 VM and right now we take 20 Hours to make a full backup.
We need to fast it up a lot.
The differential backup need 5 hours to backup 350GB.

Do you know where i can find some data about HTTP handler on XCP/Xenserver? How much GB can be fetch in the handler?

What do you mean with HTTP? can you be more specific with HTTP limitations?

With the 10Gb nic the issue is worse. Now we have the backup with 4-5 packets around 700MB and then 10-15 second with few KB, and then again 4-5 packets around 700MB.
Before we didn't have that much time without high transfer speed, i think because 10Gb nic can send more with less packets.

XOA backup.
We start a backup of a turned off Windows server 2016.
When we try to copy from a NAS to the same NFS share we don't have the same issue.

We checked the network interface status and we found that the network work as the attached picture.

Is that normal? it goes up and then to 0 and then up again, etc...
(this test is new and we used a 1Gb nic, to find if XOA use the 1Gb nic to its full)

We will try the 10Gb soon.

What do you mean with export speed of the host?
10Gb nic or 1Gb nic are the same for XCP-ng or XOA? As i can see if I use 1Gb or 10Gb nothing change and the performance are bad in both cases.