Proxmox and Veeam Backup and Replication worker issue

acsinc

New Member
Apr 6, 2026
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Vmware Esxi 6.7
Proxmox 9.0.6
Veeam 12.3.2.4465

I added a Proxmox host to Veeam and then tried to create a worker. When I do it takes a few minutes and then says:"Failed to deploy the worker VM: Cannot access a closed Stream.""Worker *myworkername* test failed: Cannot access a closed Stream.Proxmox is a fresh install with all of the non-enterprise updates applied. I set up the server and then tried to restore a vm from Veeam to it. It failed creating the worker.




I opened a case with Veeam and this was their response. In my wireshark test I didn't detect any packets on port 10006 or 19001. The commands to verify communication they suggested worked fine.

"Thank you for the information.


We have finished our analysis and have found several log snippets. We have outlined them below for your review with additional information.


snippet 1 showing the full error in question, nothing special but its definitely a worker issue
2026-04-02 13:37:26.1921 00059 [2656] ERROR | [Worker][dc1185c3-bac9-46de-9d62-3e5988f8b66b][Veeam]: Worker Veeam test failed: Cannot access a closed Stream.


snippet 2 showing additional detail around the error. It is occurring during API communication with the Proxmox server
2026-04-02 14:15:36.6516 00010 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: <== Request "Post" "https://192.168.0.65:8006/api2/json/nodes/proxmox/storage/local/upload", body: "{}"
2026-04-02 14:15:36.6516 00010 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: ==> Response "Post" "https://192.168.0.65:8006/api2/json/nodes/proxmox/storage/local/upload", "status: Error", duration: "44 msec", body: """"
2026-04-02 14:15:36.6516 00010 [2656] ERROR | [Worker][dc1185c3-bac9-46de-9d62-3e5988f8b66b][Veeam]: Failed to deploy the worker VM: Cannot access a closed Stream.: System.ObjectDisposedException: Cannot access a closed Stream.


snippet 3 showing an API error with the Proxmox node that it cannot get a list of the VMs
2026-04-02 14:25:50.1010 00099 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: Failed getting list of VMs: An exception occurred while processing the API request. HttpErrorCode: 596, HttpRequestError: Unknown. Message: Veeam.Vbf.Rest.Common.ClientGeneration.ApiException: An unknown Proxmox VE error has occurred


snippet 4 shows permission denied during ssh communication with the Proxmox node
2026-04-02 14:25:50.1010 00099 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: Failed getting list of VMs: An exception occurred while processing the API request. HttpErrorCode: 596, HttpRequestError: Unknown. Message: Veeam.Vbf.Rest.Common.ClientGeneration.ApiException: An unknown Proxmox VE error has occurred


snippet 5 showing a code 596 connection timeout message during API communication. This is an HTTP error of 596 which is not a standard error . 596 errors are used by specific platforms and libraries to indicate internal proxy or connection failures.
2026-04-02 11:12:01.7335 00106 [2656] ERROR | [ProxmoxExtensions][0HNKGN2LN5NP9:00000008]: <== Request "Get" "https://192.168.0.65:8006/api2/json/nodes/proxmox/storage", body: "{}"
2026-04-02 11:12:01.7335 00106 [2656] ERROR | [ProxmoxExtensions][0HNKGN2LN5NP9:00000008]: ==> Response "Get" "https://192.168.0.65:8006/api2/json/nodes/proxmox/storage", "code: 596 - Connection timed out", duration: "30 sec 71 msec", body: ""


All of these message indicate potential connectivity issues between the hosts. Please run the below commands to verify network communication.


Test-NetConnection -ComputerName <proxmox node IP> -Port 8006
Test-NetConnection -ComputerName <proxmox node hostname> -Port 8006
Test-NetConnection -ComputerName <proxmox node IP> -Port 22
Test-NetConnection -ComputerName <proxmox node hostname> -Port 22


Also during worker deployment doing a packet capture on the VBR server to see if there are any packets coming inbound on ports 10006 and 19001 indicating the worker can communicate with the VBR server should be done as well. We suggest Wireshark but you can use whatever method is approved by your organization. We have attached articles below on ports used and example port tests."


My goal is to evaluate if Proxmox is a suitable replacement for our Esxi 6.7 host and this issue is standing in the way.
 
Hi @acsinc , welcome to the forum.

Veeam is a partner of PVE and they theoretically have access to PVE support to assist with common customer issues. However, you seem to be a Veeam only customer at this point. You may benefit from the help from a PVE implementation partner - they can usually assist with complex network/application integration.

All that said, I am curious about the claimed SSH errors:
snippet 3 showing an API error with the Proxmox node that it cannot get a list of the VMs
2026-04-02 14:25:50.1010 00099 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: Failed getting list of VMs: An exception occurred while processing the API request. HttpErrorCode: 596, HttpRequestError: Unknown. Message: Veeam.Vbf.Rest.Common.ClientGeneration.ApiException: An unknown Proxmox VE error has occurred


snippet 4 shows permission denied during ssh communication with the Proxmox node
2026-04-02 14:25:50.1010 00099 [2656] ERROR | [ProxmoxNode][proxmox][c72aeb00-8d89-11f0-b79a-b0e266456b00]: Failed getting list of VMs: An exception occurred while processing the API request. HttpErrorCode: 596, HttpRequestError: Unknown. Message: Veeam.Vbf.Rest.Common.ClientGeneration.ApiException: An unknown Proxmox VE error has occurred
the log snippet referenced is the same for both points that Veeam support called out. It appears to reference a JSON API request rather than SSH. However, it is also possible that Veeam is using SSH and calls it API...

@gasherbrum just brought up a good point about storage types and allowed content - I've been bitten by that in our lab as well.

You can also check /var/log/pveproxy/access.log - tailing it during the connection attempt could bring some clarify about the origin of the error.

Additionally, check the MTU consistency - I don't thing the "test-connection" exercises enough data/sizes to detect MTU issues.



Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox
 
post your /etc/pve/storage.cfg


Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox
dir: local
path /var/lib/vz
content import,vztmpl,snippets,rootdir,images,iso,backup
shared 0

lvmthin: local-lvm
thinpool data
vgname pve
content images,rootdir

esxi: ACS
server 192.168.1.14
username administrator@vsphere.local
content import
skip-cert-verification 1

esxi: ACS-16
server 192.168.1.16
username root
content import
skip-cert-verification 1

esxi: ACS-18
server 192.168.1.18
username root
content import
skip-cert-verification 1
 
I recommend that you figure out a curl based way to upload a file to local storage with the same account that Veeam is using. Run it local to PVE first, if that works - run it from the Veeam network segment. If that works, convert it to PS command and test from Veeam server.
Network issue is still the primary suspect based on your posted material.



Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox
 
I'm digging further into network issues. When I ping the proxmox server from the veeam server I see 20ms pings. That should be 1 or 2 ms. I had a 2 port poe switch in the mix that was casuing that.

Edit: Took the poe switch out and back to <1 ms pings. The worker deployed the first try no problems so it was a networking issue. Hopefully this thread helps someone in the future. Thanks everyone for your input.
 
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