This is really odd. I've replaced ethernet cables and what not, but most of the time, when I try to connect to the MBP on my LAN, it will initially disappear from the sidebar before reappearing. The errors in my system log look like this:
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: NAHSelectionAcquireCredential complete: iakerb 139410F5-F9D9-EDFD-BB1B-3ECBA8EAE6C1 - <email>: GSSCred: 0x7fe9fbe34b50 <MC: iakerb
com.apple.idms.appleid.prd.74344e736...COM.APPLE.LKDC>
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: major error <1> Miscellaneous failure (see text)
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: ERROR: AFP_OpenSession - Login failed with 80
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: NAHSelectionAcquireCredential complete: iakerb 4FA4488A-C348-4E76-56BF-15BBBBB9872D - <user>: GSSCred: 0x7fe9fbd5ceb0 <MC: iakerb <user>@WELLKNOWN:COM.APPLE.LKDC>
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: major error <1> Miscellaneous failure (see text)
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: ERROR: AFP_OpenSession - Login failed with 80
Mar 23 02:18:57 Musa.local NetAuthSysAgent[22122]: NAHSelectionAcquireCredential The operation couldn’t be completed. (com.apple.NetworkAuthenticationHelper error -1765328228 - acquire_kerberos failed <user>@LOCAL: -1765328228 - unable to reach any KDC in realm LOCAL, tried 0 KDCs)
Mar 23 02:18:59 Musa.local Screen Sharing[22123]: No valid display name
Mar 23 02:19:01 Musa.local NetAuthSysAgent[22122]: NAHSelectionAcquireCredential The operation couldn’t be completed. (com.apple.NetworkAuthenticationHelper error -1765328372 - acquire_kerberos failed
com.apple.idms.appleid.prd.74344e736...COM.APPLE.LKDC: -1765328372 - KDC policy rejects request)
I've done some searching on the web for this sort of error, and found
this article.
But I don't think that the issue is password incompatibility or out-of-date caches. I'm also a bit confused as to why Kerberos is involved in these AFP connections.
In any case, I'm fresh out of ideas as to how to fix this problem. I've tried repairing my keychain (no errors) and deleting all keychain entries pertaining to the remote MBP, and initially they seem to help, but then the previous behavior returns.