Upload files speed problems


I'm trying to upload a file to a datastore via vsphere client, and i'm getting ultra slow performance. About 2Mb/s.

This is my scenario:

VCenter Server

2 x ESXi 4.0 Update 2

Single Windows 2008


All the host are attached to 1Gigabit connections.

No traffic shapping or any kind of configuration limits.

I've checked speed and duplex an all nics are at 1000 full.

The DataStore is in a iSCSI SAN working perfectly (backups speed are really good)

The DataStore doesn't contain any VM.

I've tried VeeamFast SCP and the result are the same.

Are some kind of limitation using the the vSphere Client File Management API ?

Can you give some steps to do some troubleshooting?

I need to speed up this transfer because I need to use VeeamBackup Replication and uses the same API to do the replication job.

Please let me know if you need more info.

Thanks in advance.

Tags (2)
0 Kudos
3 Replies
VMware Employee
VMware Employee

When you upload from the VSphere Client, it is basically a network copy from the machine you are on to the Datastore.

If you network backups for the VMs are fast, which proves the Network is fine, the issue must be on the VSphere Client machine

Things I can think off:

Try to copy from the backup server to the data-stores.

Might be a firewall issue on the current client

Make sure Wireless is off and copper network card is definitely use (long shot :smileycool: )

Hope it helps


If you find this or any other answer useful please consider awarding points by marking the answer helpful or correct. Thank you.


I'm doing the test in the backup server, not direclty from my desktop.

I'm going to check if there is a firewall issue.

Do you know something more that i can check?

0 Kudos


Firewall issue discarded, I've done the test with firewall disabled and the speed is the same.

0 Kudos