On Tue, Dec 05, 2017 at 05:47:22PM +0000, Sebby, Brian A. wrote: > I’m working on finally upgrading our AFS cell from DES to stronger encryption > keys, and I was able to successfully follow the instructions on the OpenAFS > web page to get a new keytab issued for my test cell with stronger encryption. > > However, after installing the new keytab file on my test AFS servers and > restarting the processes, I found that tokens that had been issued with my > previous key were no longer working - I had to do a kinit with the updated > Kerberos principal and run aklog again to get a working token. > > My goal would be to make sure that existing tokens didn’t stop working when I > upgrade my production cell, so I’m wondering if I did something wrong or > accidentally disabled something too early. Here are the steps I ran: > > > 1.) Have new keytab created by our AD admin that has all of the newer > encryption types, as well as the older DES encryption, with a new KVNO. > > 2.) Removed the DES keys from the keytab file. > > 3.) Deploy the new keytab file to all of my servers as rxkad.keytab. The > old KeyFile was still in place.
The combination of 2 and 3 is probably suboptimal, in that you no longer have access to the DES key of the new kvno. OpenAFS will attempt to look for it in the KeyFile when receiving a DES-encrypted ticket using that kvno, so it's best to keep it in the rxkad.keytab (even thoug it will not be used from there by AFS; just to keep all the keys in one place), and also use 'asetkey add' to insert the new DES key into the KeyFile. > 4.) Restarted the AFS servers. > > 5.) Ran kinit, and verified that the afs/<cell>@<REALM> key was still > listed as des-cbc-crc. By using kvno(1) or aklog or what? Did the resulting token work? (I expect it to not work even here.) > 6.) Had the AD admin unset the ‘DES only’ box on the account tied to the > afs/<cell>@<REALM> identity. > > 7.) Restarted the AFS servers again. > > 8.) Ran kinit again, and verified that the afs/<cell>@<REAM> key is now > listed as one of the higher encryption types. Again, via aklog or kvno(1) or otherwise? > 9.) Ran aklog, verified that I could write to AFS. > > 10.) Tried to write with session that had an older token, and got permission > denied. After re-kinit-ing, it worked as expected. This older token is one from circa step 5? > I am planning to do the cell upgrade on a weekend to minimize the potential > disruption, but I would still like to have my old tokens work if possible. > Did I do something wrong or restart any servers too early? You should be able to get a more seamless upgrade than that, with old tickets/tokens continuing to work until they expire. -Ben _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
