[Samba] Kerberos ticket lifetime

[Jason Keltz]

On 10/2/2020 8:05 AM, Rowland penny via samba wrote:

> On 02/10/2020 13:01, Jason Keltz via samba wrote:
>> On 10/2/2020 5:25 AM, Rowland penny via samba wrote:
>>
>>> On 01/10/2020 21:46, Rowland penny via samba wrote:
>>>> On 01/10/2020 21:23, Jason Keltz via samba wrote:
>>>>>
>>>>>
>>>>> Okay - I guess the failure of kdc: lines in smb.conf is a bug.
>>>>>
>>>>> Let's wait and see what happens with your ticket after 10 hours. 
>>>>> Maybe there's a bug there as well.
>>>> It will be in the middle of the night here, so I will report back 
>>>> in the morning, but if it is a bug (not refreshing, that is), then 
>>>> it is an RHEL one, it works on Debian.
>>>
>>> OK, I still have a valid kerberos ticket, it just doesn't seem to 
>>> have been refreshed when I expected :-\
>>>
>>> Old ticket:
>>>
>>> Ticket cache: FILE:/tmp/krb5cc_10000
>>> Default principal: rowland at SAMDOM.EXAMPLE.COM
>>>
>>> Valid starting     Expires            Service principal
>>> 01/10/20 15:34:44  02/10/20 01:34:44 
>>> krbtgt/SAMDOM.EXAMPLE.COM at SAMDOM.EXAMPLE.COM
>>>     renew until 08/10/20 15:34:44
>>> 01/10/20 15:34:44  02/10/20 01:34:44  CEN8$@SAMDOM.EXAMPLE.COM
>>>     renew until 08/10/20 15:34:44
>>>
>>> New ticket:
>>>
>>> Ticket cache: FILE:/tmp/krb5cc_10000
>>> Default principal: rowland at SAMDOM.EXAMPLE.COM
>>>
>>> Valid starting     Expires            Service principal
>>> 02/10/20 06:41:20  02/10/20 16:41:20 
>>> krbtgt/SAMDOM.EXAMPLE.COM at SAMDOM.EXAMPLE.COM
>>>     renew until 08/10/20 15:41:17 
>>
>> In your case, did you ssh to "centos8", or you just logged into it 
>> via a GUI?  When I login via the GUI, winbind renews the key. When I 
>> ssh, it does not.  On your destination system, the ticket cache is 
>> still /tmp/krb5cc_UID, and not /tmp/krb5cc_UID_<random bits>.
>>
>> In my case, even after I copied the /tmp/krb5cc_UID_<random bits> 
>> back to /tmp/krb5cc_UID, winbind also did not renew the key. sigh.
>>
>> Jason.
>>
>>
> I logged in via 'ssh' and until I added pam_krb5, I didn't get a 
> ticket. I think your problem is the lack of pam_krb5
>
But I ssh to the system and the ticket already forwards.  The problem is 
just that winbind isn't automatically renewing the ticket.   Do you have 
"forwardable=true" in /etc/krb5.conf, and did you use "ssh -K <host>" or 
do you have GSSAPIDelegateCredentials enabled?

Jason.