I'm also seeing the following error at time (with just the username, no domain), which is not mentioned in the trouble shooting doc.
Access is denied
have you setup a domain trust between domain and Orion server? Otherwise authentication simply reject the credentials (not just the IPAM). We need to set trust between the Orion/IPAM server to talk to remote DHCP server in different domain.
There's no domain trust between the two domains and I'm told that it's not an option to set one up in the past. I've seem no issues with SAM monitoring between the two domains or to stand alone systems, so I'm confused why IPAM has this requirement when SAM does not.
The documentation says create local accounts the same, but leaves out any detail of how to complete this.
I had a similar situation recently that I was able to work around and get cross domain authentication for DHCP monitoring working with NO trust between the domains.
In attempting to configure this I found it quite suprising that the NPM core AND DNS monitoring withing IPAM BOTH worked fine using Untrusted_Domain\User with no problem.
However, every attempt to authenticate against the DHCP server in the target, untrusted domain from the Add DHCP server menu in IPAM failed.
What I was finally able to get to work was to leverage classic Windows Passthrough Authentication. To achieve this I created an account locally on the NPM server with the same username and password as the target domain account.
I then REMOVED (yep, even though the instructions specifically state to include it) the "Untrusted_Domain\" portion of the credential and left ONLY the username for the target domain.
This worked with no errors and allowed me to import and monitor the target DHCP server in the remote domain with no trust between domains.
Hope this helps!
Loop1 Systems: SolarWinds Training and Professional Services