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(First question, please be patient)

We have a SonicWall NSA-2400 appliance as our firewall within our primary location. (SonicOS Enhanced

Remotely we have 2 sites with Cisco 2800 routers.

We have a working VPN between the SonicWall and the individual remotes, but machines at the remote locations are unable to authenticate with the PDC that is located in our main facility behind the SonicWall.

Devices at the remote location can ping anything behind the Sonicwall, but the windows Auth continues to fail.

Primary site (10.0.0.x) Remote A (10.0.5.x) : Can access anything on 10.0.0.x Remote B (10.0.6.x) : Can access anything on 10.0.0.x

What am I missing? Seems familiar to the old 'Black Hole Router' problem where you had to adjust the MTU setting to something <1500. thx

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Once you have identified the problem you can answer the question yourself. – FortunateDuke Jul 30 '09 at 2:23

All three sites can in the least ping each other, but authentication from one site is not working?

In which case, do you have access to the config on the two 2800's, and the Sonicwall?

I would guess that there's either some difference between 2800-A and 2800-B, or the ruleset on the Sonicwall for site A doesn't match the ruleset for site B

My initial thoughts would be that something along the lines of LDAP(s) and\or Kerberos is currently denied from main office to site with problems

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You need to open the LDAP ports, at least: 139 and 445.

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