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15 votes

Automatic Kerberos Ticket Renewal (Indefinitely)

It's the end of 2018 and I've run into the same question as you. After some digging, I can offer a write-up for posteriority. tl; dr: "Infinite renewal" not possible and probably never will be SSSD ...
fat-lobyte's user avatar
6 votes
Accepted

MIT Kerberos keeps asking for password when authenticating to OpenSSH

Root login Judging from your supplied log files I would say that the attempted root login is not your issue here. Notice that all of the authentication attempts as root come from 218.65.30.30, a ...
rlf's user avatar
  • 365
6 votes
Accepted

Kerberos error while initializing kadmin interface from admin server

I've run into the same problem (same Debian and krb5-admin-server versions). The same as you, it wasn't working when I ran kadmin from the kerberos admin server itself, which rules out time ...
JimmyL's user avatar
  • 76
4 votes
Accepted

How to force kerberos to use in memory credential cache?

As explained in the linked document, the memory cache is using MEMORY keyword so the following should do the job: default_ccache_name = MEMORY: But note that this type of ccache will be destroyed ...
Jakuje's user avatar
  • 10.1k
3 votes
Accepted

Kerberos rdns=false Breaking Connections From Linux Clients to Windows IIS Server

But isn't this error coming from the IIS webserver? No, it's coming from the GSSAPI library (libkrb5) used by curl. Why does a client's configuration setting impact the webserver's functionality? ie-...
u1686_grawity's user avatar
3 votes

Why the reverse DNS lookup of SPN during initial phase of Kerberos authentication?

I've always assumed it's to break CNAMES.
Chalky's user avatar
  • 151
3 votes

How to set Openssh and Mit kerberos (from windows to linux server)?

I'm adding a late answer since this is question is still one of the top google results for connecting to an OpenSSH SSH / SFTP / SCP server via kerberos. The short answer is try ssh -K MyServer, and ...
Cpt.Whale's user avatar
  • 412
3 votes

Is it possible to change an MIT Kerberos password programmatically?

When a user changes their Active Directory password, I would like to sync it back into MIT Kerberos. In its current form, this is too vague of a statement for it to really be answered in one shot. ...
Ryan Ries's user avatar
  • 55.9k
2 votes
Accepted

What changes with Kerberos authentication in IPv6 when everyone has a public IPv6 Address?

The same way as with IPv4, but with AAAA records instead of A records. Use IP6.ARPA instead of in-addr.arpa if rDNS is part of your setup. If you were port forwarding before, you don't have to do ...
84104's user avatar
  • 13.1k
2 votes
Accepted

How to change ccache type of MIT Kerberos

You'll want to alter the KRB5CCACHE environmental variable. Usually you'll do this for all instances in krb5.conf as follows: [libdefaults] default_ccache_name = KEYRING:persistent:%{uid} However, ...
84104's user avatar
  • 13.1k
2 votes

Kerberos ticket cache location on windows for multiple users

A ~ tilde occurring as the first character of an argument in Unix/Linux shell/bash is the same as the $HOME environment variable. Windows equivalent is %USERPROFILE%. You can use any user variable ...
JosefZ's user avatar
  • 1,584
2 votes

Using same password for kerberos and openldap

Convention has is that a Kerberos realm will be the same as the domain, but capitalized. This is not a requirement, but it does help to avoid some confusion. A kerberos principal can only have one ...
84104's user avatar
  • 13.1k
2 votes
Accepted

Use cases for kerberos credential cache type MEMORY?

The answer to this question is exactly what was postulated in the comments. From your code you can include the krb5.h header. This will give you access to the functions that make up the Kerberos code ...
rlf's user avatar
  • 365
2 votes
Accepted

Single sign on using SSSD against OpenLDAP server with Kerberos SASL/GSSAPI

Abstract After some tries and error I found that I need one package for gssapi and four packages for sssd. I want to have general configuration centralized so I use a local private dns server for name-...
Ingo's user avatar
  • 485
2 votes
Accepted

Server Not Found in Kerberos database - where is the database located?

Finally got this working. The critical pieces Reverse DNS must match Forward DNS The SPN (Service Principal Name) must be explicitly added in some cases - merely joining to the Active Directory ...
Nathan's user avatar
  • 326
2 votes

Globally disable reverse DNS lookup for Kerberos on Windows?

Unfortunately no. Implementations that use a krb5.conf style configuration can use directives like dns_canonicalize_hostname = false [1] and the builtin java krb5.conf does support this directive. But ...
squarewav's user avatar
  • 140
2 votes
Accepted

sudo with Kerberos credentials

Running the command with sudo or similar is actually a fairly good approach – it provides UID-based separation to prevent the invoker from accessing the temporary tickets. You could avoid the need for ...
u1686_grawity's user avatar
1 vote

Putting .k5login credentials in ldap with freeipa

It is not implemented anywhere, thus not available. However, I'd recommend against using this approach. Aside from convenience you would be losing audit of the actions performed. Going with sudo rules ...
abbra's user avatar
  • 1,158
1 vote
Accepted

ubuntu ignores default_ccache_name

always defaults to FILE:/tmp/krb5cc_<UID>_<VALUE> If KRB5CCNAME points to a cache with a random suffix, this indicates that some software has decided to explicitly set up an isolated ...
u1686_grawity's user avatar
1 vote
Accepted

MIT Kerberos renew lifetime does not work

The solution: there are 4 settings (5 to be exact but the 5th is the kinit -r TIME parameter itself) where the minimum of all is taken: krb5.conf: REALM = { max_renewable_life = 7d } kdc.conf: REALM ...
comfix's user avatar
  • 11
1 vote

Migrating from Heimdal to MIT Kerberos

Here's what I have so far: Dump the Heimdal database. According to the old Heimdal docs, it should be possible to simply dump the db in MIT format using kadmin -l dump -f MIT. But the build of ...
stevegt's user avatar
  • 240
1 vote

Kerberos KDC server in a docker container

You should check the config file, kdc.conf. That will tell you where the files are stored that are being used. exec into the container when it's running and find the kdc.conf file. Also the krb5....
J Roysdon's user avatar
  • 161
1 vote

Kerberos KDC server in a docker container

Isn't just enough to mount the volume to the container's default KDC database path like docker run -v /var/local/docker-volumes/krb5kdc:/usr/local/var/krb5kdc <kdc_image>? Or you can specify ...
patok's user avatar
  • 692
1 vote

Cross-Realm-Trust between Active Directory and MIT Kerberos

Fair warning, my knowledge in this area is extremely dated at this point. Like early 2000's, Windows 2003 era Active Directory. So things may work differently now. The main problem is that Windows ...
Ryan Bolger's user avatar
  • 16.9k
1 vote
Accepted

What does it mean to "add" a principal to a keytab file in Kerberos?

A key table (keytab) file contains pairs of Kerberos principal identities and a corresponding encrypted key for that principal. It is as good as a password (and should be secured as such), and can be ...
Cosmic Ossifrage's user avatar
1 vote

MIT Kerberos keeps asking for password when authenticating to OpenSSH

There are several things to consider: 1. Can you get the service ticket on your client machine? Verify that you can get the ticket for the service you want to use. For SSH this is usually host/@...
Andreas Rogge's user avatar
1 vote
Accepted

Which servers to copy keytab file to

in a normal situation, the keytab file you created (usually, using a service account principal (or instance), for example ssh/hostname) should be placed on the "client" of that kerberos service. and ...
olivierg's user avatar
  • 544
1 vote
Accepted

Apache Kerberos Authentication : KDC has no support for encryption type

It was indeed due to the activation of the DES support in AD. This actually override any other cipher algorithms. So disabling it on the service account made the negociation works in AES256.
Plup's user avatar
  • 161
1 vote

Kerberos error while initializing kadmin interface from admin server

Check that you have opened kdc ports on the server (749 by default, both tcp and udp) and that the client can connect to it. This was the problem for me that resulted in kadmin: Communication failure ...
SergioLeone's user avatar
1 vote

Windows - Kerberos SSO from outside the domain

I recently got KERBEROS working from a VPN-connected workstation that's not joined to the domain (an AWS-managed Server 2008R2 Active Directory). The key was adding the SRV and corresponding A records ...
Gordy's user avatar
  • 111

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