topic Re: Only connecting to read-only domain controller during CIFS setup in Network and Storage Protocols

Only connecting to read-only domain controller during CIFS setup

paul_w_jackson — Thu, 05 Jun 2025 06:59:08 GMT

Hi,

I'm trying to add a controller (at a remote site) to our active directory domain but I keep getting an error that the AD account we're using doesn't have permissions. We ran a pktt capture and found that the filer is only communicating with the read-only domain controller (which is in close proximity). This is a problem because it's read-only and can't be updated. Is this normal behavior? I would think that it should recognize that it's a read-only DC and move on to the read/write domain controller (which is at our primary datacenter). Any help would be appreciated. Thanks.

Re: Only connecting to read-only domain controller during CIFS setup

thomas_glodde — Mon, 28 Feb 2011 19:25:03 GMT

possible some sorta bug/missing feature. during cifs setup filer is doing a dns/wins/ldap site query and chooses the closest dc possible. maybe a quick fix would be to shut down that read only dc, do setup, and then boot up again.

Re: Only connecting to read-only domain controller during CIFS setup

paul_w_jackson — Mon, 28 Feb 2011 19:34:46 GMT

That's what we're thinking--either shutdown the local r/o DC or maybe add an incorrect route to that DC on the filer. Will let you know how that works.

Re: Only connecting to read-only domain controller during CIFS setup

paul_w_jackson — Tue, 01 Mar 2011 15:39:11 GMT

Well, taking down the R/O DC at our remote site which has the filer in question and then running CIFS setup fixed the problem. Our team is still convinced that NetApp's OS doesn't handle read-only DC's correctly. Does anyone else have experience here? We're trying to complete our RCA. Thanks.

Re: Only connecting to read-only domain controller during CIFS setup

spence — Tue, 01 Mar 2011 15:55:32 GMT

cifs setup creates a computer account or reuses a computer account that has been pre-created and then sets the machine account password.

Next time use cifs prefdc and specify a writable DC, run cifs setup and then change cifs prefdc to use the local RODC.

Re: Only connecting to read-only domain controller during CIFS setup

thomas_glodde — Tue, 01 Mar 2011 17:27:35 GMT

cifs prefdc is usualy the way to go but i think you cannot use cifs prefdc before actualy having done a cifs setup at all. i might be wrong tho.

Re: Only connecting to read-only domain controller during CIFS setup

spence — Tue, 01 Mar 2011 18:48:45 GMT

you can use cifs prefdc prior to running cifs setup.

Re: Only connecting to read-only domain controller during CIFS setup

paul_w_jackson — Wed, 02 Mar 2011 17:49:26 GMT

We used cifs prefdc to specify a read/write DC but after running CIFS setup our packet capture confirmed that it was still only connecting to the local RODC. Possibly a networking issue or a bug in DataOnTap.

Re: Only connecting to read-only domain controller during CIFS setup

kao_lance — Wed, 18 Jul 2012 13:55:11 GMT

I had problems trying to join a filer in a remote site with an RODC to the domain too. cifs domaininfo showed me all DCs as "BROKEN". What I did was set the site for the filer's IP to my RWDC site in AD Sites and Services... once that propagated, I was able to join my filer without a problem. Question now is do I leave it this way and will it impact performance?