Active Directory Sync Error


New Member
Jul 5, 2023
I am trying to simply follow the tutorial to connect my Proxmox server to an Active Directory that is being run in one of my VMs. When I follow the steps to connect to the AD, when I attempt to Sync after adding the AD to the Realms, I get a "TASK ERROR: Protocol not available". I have searched quite a bit, and I haven't seen anyone else have this issue. I am sure I am making some rookie mistake, but if someone could point me in the right direction it would be greatly appreciated. Thanks!
FYI: This is Proxmox 7.1-7.
Last edited:

could you share the realm configuration from /etc/pve/domains.cfg?

pam: pam
comment Linux PAM standard authentication

pve: pve
comment Proxmox VE authentication server

ad: ad
domain ad.local
bind_dn CN=Admin,OU=Local Admins,DC=ad,DC=local
default 0
secure 0
sync-defaults-options full=1,scope=both
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Whenever we attempt to Preview or Sync the AD after adding it to the realms, it immediately fails with the TASK ERROR: Protocol Not Available. It doesn't even attempt to try and reach the server, so I'm not sure what protocol it is referring to. If I knew the protocol that wasn't available, I could try some fixes, but I don't know what protocol it is attempting to use that it just doesn't have.
Hmmm, I've attempted to recreate the issue. My AD config pretty much looks exactly like yours, but for me it works:

ad: ad
    bind_dn CN=Administrator,CN=Users,DC=ad,DC=example,DC=com
    default 0
    secure 0

Do you have any other clients that already use the AD successfully? At this point I'd suspect some misconfiguration on the AD side.


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