So when my code runs in a NiFi processor, the initial keytab authentication works fine but following that it seems to think keytabs aren't in use (UserGroupInformation.getCurrentUser.isFromKeytab is false), which explains why the renewal code never actually runs and why re-login is attempted using the ticket cache after the GSS exception. Over to the NiFi list I think...
Making some progress! On 13 July 2017 at 18:28, Josh Elser <els...@apache.org> wrote: > Aha! That's an interesting wrinkle :) > > I have more experience with NiFi's use of Kerberos than I care to admit (due > to some folks who work in the physical office I do); I'm not aware of > anything that NiFi does which would cause problems, but that may be a > relevant detail. > > After I thought about it some more (to your #2 point): there's a little > failsafe in the Accumulo client implementation that, upon a SASL > authentication failure, it will attempt a relogin via Kerberos. This should > "catch" the cases where your client application is using a ticket cache > (because convention on the ticket cache location lets the jGSS client > library in Java itself do the relogin whereas Java doesn't know which keytab > to use). Still though -- a thread as you describe in #1 should have an > equivalent net-effect.. > > On 7/13/17 11:45 AM, James Srinivasan wrote: >> >> Thanks, just checked that and it does seem renewable (tested using >> kinit -R). I'm running my code in two separate scenarios: >> >> 1) As part of a NiFi processor, which currently makes multiple >> Accumulo connections using the same keytab, each of which currently >> has a separate renewer thread >> 2) As part of a simple command line application - this seems to have >> no problem running for > 10 hours (even before I added the periodic >> renewal code) >> >> Will add extra logging to #2 and try to shorten the expiry from 10 >> hours to 1 so I can see any difference in output. >> >> James >> >> On 13 July 2017 at 16:05, Josh Elser <els...@apache.org> wrote: >>> >>> It also may be worth mentioning to check the principal's configuration >>> that >>> you're using in your client. Depending on which you're using and how it >>> was >>> created, it may not actually support renewals. >>> >>> A quick test is to just `kinit` and then `kinit -R`. You can view the >>> explicit "configuration" for a principal using the `kadmin` console and >>> the >>> `getprinc <principal>` command. Be sure to check the krbtgt/<REALM> >>> principal as well: >>> >>> e.g. >>> >>> kadmin.local: getprinc jelser >>> Principal: jel...@example.com >>> Maximum ticket life: 1 day 00:00:00 >>> Maximum renewable life: 7 days 00:00:00 >>> >>> kadmin.local: getprinc krbtgt/EXAMPLE.COM >>> Principal: krbtgt/example....@example.com >>> Maximum ticket life: 1 day 00:00:00 >>> Maximum renewable life: 7 days 00:00:00 >>> >>> If the krbtgt/$REALM principal does not have a non-zero renewable >>> lifetime, >>> any other principals created in that realm would also not be allowed to >>> be >>> renewed. Since you have the working "service" principals, you can >>> cross-check those. >>> >>> On 7/13/17 10:56 AM, James Srinivasan wrote: >>>> >>>> >>>> Yup, I am indeed on HDP - thanks for the link. The services do log GSS >>>> exceptions every ten hours, but seem to sufficiently recover >>>> themselves. Having turned up logging on my client: >>>> >>>> 1) On client start, I see hadoop login messages >>>> 2) After 8 hours (0.8*10 hours) when the renewal is expected to take >>>> place, I don't see any hadoop login messages >>>> 3) After 10 hours, I see GSS exceptions >>>> 4) After each GSS exception, I see an attempt to renew but using >>>> ticket cache, rather than keytab. >>>> >>>> Currently working on shortening the 10 hour expiry time so I can catch >>>> it in a debugger! >>>> >>>> Thanks, >>>> >>>> James >>>> >>>> >>>> On 13 July 2017 at 15:20, Josh Elser <els...@apache.org> wrote: >>>>> >>>>> >>>>> If you're using Hortonworks' HDP, you would probably benefit from >>>>> https://github.com/hortonworks/accumulo >>>>> >>>>> There is likely a git-tag for the exact version that you're running. >>>>> The >>>>> line numbers would match there. >>>>> >>>>> To be clear, if your services (e.g. TabletServers) aren't failing after >>>>> 10hrs, you're not running into ACCUMULO-4069. Given my (limited) >>>>> understanding, your problem is purely client-side. It's possible that >>>>> the >>>>> client-side RPC implementation isn't correctly handling the ticket >>>>> re-login, >>>>> but I know there is specifically code in there to handle the re-login >>>>> case. >>>>> >>>>> The next step would be getting some debug logging from your application >>>>> around UserGroupInformation or the JDK itself, or just spin up a >>>>> trivial >>>>> example with a small relogin window to reproduce the problem. >>>>> >>>>> On 7/12/17 3:48 PM, James Srinivasan wrote: >>>>>> >>>>>> >>>>>> >>>>>> Yup, I'm going to spin up a vanilla 1.7.0 (maybe newer) install too to >>>>>> see if it behaves any differently. There is at least one patch >>>>>> included in their distro that isn't in the formal documentation, plus >>>>>> it makes matching line numbers in logs to src code rather difficult. >>>>>> >>>>>> Thanks, >>>>>> >>>>>> James >>>>>> >>>>>> On 12 July 2017 at 20:37, Sean Busbey <bus...@cloudera.com> wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> Hi James! >>>>>>> >>>>>>> It sounds like you may need to chase things down with your vendor, >>>>>>> since the precise combination of patches included will make looking >>>>>>> at >>>>>>> things hard for the community. >>>>>>> >>>>>>> On Wed, Jul 12, 2017 at 11:01 AM, James Srinivasan >>>>>>> <james.sriniva...@gmail.com> wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> Hi, >>>>>>>> >>>>>>>> So I've fired off a thread to perform the periodic >>>>>>>> checkTGTAndReloginFromKeytab call which seems to be running, but the >>>>>>>> connection still fails with GSS errors after precisely 10 hours. >>>>>>>> >>>>>>>> While I am running 1.7.0, it seems the vendor included the >>>>>>>> ACCUMULO-4069 patch, and immediately after the exception is thrown I >>>>>>>> see a log entry "Performing ticket-cache-based Kerberos re-login". >>>>>>>> However, it should be using a keytab - have turned up the logging to >>>>>>>> 11 and will leave running overnight... >>>>>>>> >>>>>>>> James >>>>>>>> >>>>>>>> On 11 July 2017 at 16:17, Josh Elser <josh.el...@gmail.com> wrote: >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> Nope, you've got it exactly right! That's the code I would've >>>>>>>>> pointed >>>>>>>>> you at >>>>>>>>> to copy :) >>>>>>>>> >>>>>>>>> If/when you do get to long-running MR jobs, see the >>>>>>>>> "general.delegation.token.*" configuration properties in this >>>>>>>>> table[1]. >>>>>>>>> I >>>>>>>>> think the docs are citing that one delegation token is valid for 7 >>>>>>>>> days, but >>>>>>>>> it's been a long time since writing/testing that code. >>>>>>>>> >>>>>>>>> - Josh >>>>>>>>> >>>>>>>>> [1] >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> https://accumulo.apache.org/1.8/accumulo_user_manual.html#_server_configuration_2 >>>>>>>>> >>>>>>>>> On 7/11/17 1:25 AM, James Srinivasan wrote: >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Thanks both. I can't (easily) upgrade beyond 1.7.0, but have >>>>>>>>>> raised >>>>>>>>>> a >>>>>>>>>> support case with our Hadoop distribution vendor. >>>>>>>>>> >>>>>>>>>> I'm not (yet) worried about expiration with MapReduce - for now >>>>>>>>>> I'll >>>>>>>>>> try to keep such jobs to under 24h! Outside MR, sounds like I just >>>>>>>>>> need to periodically call >>>>>>>>>> UserGroupInformation.checkTGTAndReloginFromKeytab like >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> https://github.com/apache/accumulo/blob/master/server/base/src/main/java/org/apache/accumulo/server/security/SecurityUtil.java#L121 >>>>>>>>>> >>>>>>>>>> Or is the TGT associated with an Accumulo KerberosToken separate? >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> >>>>>>>>>> James >>>>>>>>>> >>>>>>>>>> On 11 July 2017 at 02:59, Josh Elser <josh.el...@gmail.com> wrote: >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> No, you are (likely) not running into ACCUMULO-4069. What you've >>>>>>>>>>> described sounds like your client's ticket expired. Accumulo does >>>>>>>>>>> not >>>>>>>>>>> spawn any ticket renewal on the behalf of clients. >>>>>>>>>>> >>>>>>>>>>> Hadoop's UGI code will automatically spawn a renewal thread when >>>>>>>>>>> you >>>>>>>>>>> log in using a ticket cache. This does not happen automatically >>>>>>>>>>> when >>>>>>>>>>> you use a keytab (I have no explanation as to why this is). This >>>>>>>>>>> is >>>>>>>>>>> the most likely cause of your error and something you need to >>>>>>>>>>> correct >>>>>>>>>>> in your application (spawn a thread to renew your application's >>>>>>>>>>> ticket). >>>>>>>>>>> >>>>>>>>>>> If you are using MapReduce, you have yet another layer of >>>>>>>>>>> indirection >>>>>>>>>>> with DelegationTokens, but that's probably not what you're seeing >>>>>>>>>>> (as >>>>>>>>>>> DelegationTokens don't actually have a Kerberos TGT). >>>>>>>>>>> >>>>>>>>>>> On Mon, Jul 10, 2017 at 5:42 PM, Christopher >>>>>>>>>>> <ctubb...@apache.org> >>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> It certainly sounds like the same issue. I'd recommend upgrading >>>>>>>>>>>> to >>>>>>>>>>>> the >>>>>>>>>>>> latest 1.7.3 (currently the latest 1.7 version) to include all >>>>>>>>>>>> the >>>>>>>>>>>> bugs >>>>>>>>>>>> we've found and fixed in that release line. >>>>>>>>>>>> >>>>>>>>>>>> On Mon, Jul 10, 2017 at 5:50 AM James Srinivasan >>>>>>>>>>>> <james.sriniva...@gmail.com> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> I'm using Accumulo 1.7.0 and finding that after some period of >>>>>>>>>>>>> time >>>>>>>>>>>>> (>8 hours, <3 days - happened over the weekend) my ingest fails >>>>>>>>>>>>> with >>>>>>>>>>>>> errors regarding "Failed to find any Kerberos tgt". My guess is >>>>>>>>>>>>> that >>>>>>>>>>>>> the ticket from the keytab has expired, and needs to be renewed >>>>>>>>>>>>> - >>>>>>>>>>>>> from >>>>>>>>>>>>> memory, I had seen a Kerberos tgt renewer thread running in my >>>>>>>>>>>>> client, >>>>>>>>>>>>> so assumed it happened automagically. Is that the case? Perhaps >>>>>>>>>>>>> I >>>>>>>>>>>>> am >>>>>>>>>>>>> hitting this bug? >>>>>>>>>>>>> https://issues.apache.org/jira/browse/ACCUMULO-4069 >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> >>>>>>>>>>>>> James >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> busbey
