Questions tagged [kerberos]
Kerberos is a computer network authentication protocol, which allows nodes communicating over a non-secure network to prove their identity to one another in a secure manner. Its designers aimed primarily at a client–server model, and it provides mutual authentication — both the user and the server verify each other's identity.
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Can someone please explain Windows Service Principle Names (SPNs) without oversimplifying?
I have wrestled with service principle names a few times now and the Microsoft explanation is just not sufficient. I am configuring an IIS application to work on our domain and it looks like some of ...
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Why use Kerberos instead of NTLM in IIS?
This is something that I've never really been able to answer as well as I like: What is the real advantage of using Kerberos authentication in IIS instead of NTLM?
I've seen a lot of people really ...
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What is SASL/GSSAPI?
Numerous times i have met the expression SASL/GSSAPI. I have searched Google many times, but i simply do no understand what it is and how it relate to Kerberos.
Anybody that have a simple explanation ...
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Authenticating OpenBSD against Active Directory
Edit: Reformatted this as Q&A. If anyone can change this from Community Wiki to a typical question, that's probably more appropriate as well.
How can I authenticate OpenBSD against Active ...
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How does Kerberos work with SSH?
Suppose I have four computers, Laptop, Server1, Server2, Kerberos server:
I log in using PuTTY or SSH from L to S1, giving my username / password
From S1 I then SSH to S2. No password is needed as ...
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How do I get /dev/random to work on an Ubuntu virtual machine?
Apparently, /dev/random is based on hardware interrupts or similar unpredictable aspects of physical hardware. Since virtual machines don't have physical hardware, running cat /dev/random within a ...
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The Story of secure user-authentication in squid
once upon a time, there was a beautiful warm virtual-jungle in south america, and a squid server lived there. here is an perceptual image of the network:
<the Internet>
...
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Kerberos Authentication for workstations not on domain
I have a base understanding of how Kerberos works in an Active Directory environment and the methods it uses to authenticate users and workstations onto the network, but my question is.. since ...
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IPA vs just LDAP for Linux boxes - looking for a comparison
There are few (~30) Linux (RHEL) boxes and I'm looking for centralized and easy managed solution, mostly for control user accounts. I'm familiar with LDAP, and I deployed a pilot of IPA ver2 from Red ...
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Kinit Won't Connect to a Domain Server : Realm not local to KDC while getting initial credentials
I am setting up a testbed environment where Linux (Ubuntu 10.04) clients will authenticate to a Windows Server 2008 R2 Domain Server.
I am following the official Ubuntu guide to set up a Kerberos ...
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How do you find out if Active Directory is using Kerberos or NTLM?
Is there a command line program you can use?
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Linux Central Authentication/Authorization Methods
I have a small but growing network of Linux servers. Ideally I'd like a central place to control User Access, change passwords, etc... I've read a lot about LDAP servers, but I'm still confused about ...
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Why don't Active Directory user accounts automatically support Kerberos AES authentication?
I'm playing around with a test domain on Windows Server 2012 R2. I'm operating at the highest possible functional level and have no backwards-compatibility issues in my small test environment. However,...
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Getting Squid to authenticate with kerberos and Windows 2008/2003/7/XP
This is something I setup recently and was quite a big pain. My environment was getting squid to authenticate a Windows 7 client against a Windows 2008 Server invisibly. NTLM is not really an option,...
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Why is MS SQL Server Using NTLM Authentication?
Windows Server 2008 R2.
SQL Server 2008 R2 installed.
MSSQL Service runs as Local System.
Server FQDN is SQL01.domain.com.
SQL01 is joined to an Active Directory domain named domain.com.
The ...
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Kerberos ktutil, what kinds of encryption are available?
I am attempting to make a keytab using ktutil. I get to choose the encryption type, but the ktutil man page does not offer a list of possible choices. I also don't know which encryption method is the ...
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Which kerberos flavor?
So I'm setting up a small network with all the standard stuff (files, email, etc.) and I've decided to go with a Kerberos+LDAP solution. Any ideas or recommendations on Heimdal vs. MIT?
I've used MIT ...
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How to automate kinit process to obtain TGT for Kerberos?
I'm currently writing a puppet module to automate the process of joining RHEL servers to an AD domain, with support for Kerberos.
Currently, I have problems with automatically obtain and cache ...
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Putty Kerberos/GSSAPI authentication
I configured a few Linux servers to authenticate with Active Directory Kerberos using sssd on RHEL6. I also enabled GSSAPI authentication in hopes of passwordless logins.
But I can't seem to get ...
13
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2
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Automatic Kerberos Ticket Renewal (Indefinitely)
I am currently switching our environment from NIS over to Kerberos + LDAP.
During this migration I've now run into the following situation.
We mount our homes via NFS which obviously should also be ...
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Track Down Which Process/Program is Causing Kerberos pre-authentication error (Code 0x18)
We have a domain account that is being locked out via 1 of 2 servers. The built-in auditing only tells us that much (locked out from SERVER1, SERVER2).
The account gets locked out within 5 minutes, ...
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Kerberos KDC has no support for encryption type while getting credentials
I am configuring an apache/SSO authentication with an AD with Kerberos.
My http server is a Debian Wheezy and the AD is a Windows Server 2012.
I generated keytabs files on WS2012 with kpass command ...
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Retreive the current Kerberos KVNO from Active Directory
I have a Kerberos problem with a Linux host connecting to a Windows KDC. I suspect that Kerberos key with the wrong version is to blame.
One way to be shure would be to delete the SPN and create it ...
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Apache mod_auth_kerb and LDAP user groups
I've been considering deploying mod_auth_kerb on our internal web servers to enable SSO. The one obvious problem I can see is that it's an all-or-nothing approach, either all your domain users can ...
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How can I check if my IIS site is using NTLM or Kerberos?
How can I check if my IIS site is using NTLM or Kerberos? And how can I change authentication from Kerberos to NTLM? I'm using IIS 7.5.
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Adding local users / passwords on Kerberized Linux box
Right now if I try to add a non-system user not in the university's Kerberos realm I am prompted for a Kerberos password anyway. Obviously there is no password to be entered, so I just press enter and ...
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Integrated Windows Authentication with Apache HTTP Server on Linux
What is the best way to enable Integrated Windows Authentication for a PHP web application running on Apache2/Linux? There is a Windows Domain Controller in the network which should be used for ...
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Multiple Realms and Multiple TGTs under MIT Kerberos for Windows
My local computer uses Windows 7 Pro and belongs to realm LR, managed by AD servers. I login to my computer while attached to that realm's network. I can view the TGT with MIT Kerberos for Windows ver....
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How to tell mod_auth_kerb to do its job despite no "require valid-user"
I implemented a SSO authentication using mod_auth_kerb on Apache. My config looks like this:
<Location /login/ >
AuthType Kerberos
AuthName "Kerberos Login"
KrbMethodNegotiate on
...
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Permissions to create an spn
According to some of the documentation I've read the service account for SQL server will create an SPN when the database engine starts up, allowing for kerberos authentication. I haven't been able to ...
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keytab auth against samba 4 DC: Client not found in Kerberos database while getting initial credentials
I set up a samba 4 active directory on ubuntu 14.04 following Samba AD DC HOWTO. In principle everything works well but I'm stuck in getting kerberos authentication running using SPNs for web ...
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How can I log into a Domain controller that doesn't trust itself
I have a windows 2008 R2 standalone Domain Controller that I restored from backup. The original DC is offline.
When I log in with valid user credentials I get the error:
"The security database on ...
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How to integrate Active Directory with FreeBSD 10.0 using security/sssd?
What are the required steps to authenticate users from an Active Directory running on Windows Server 2012 R2 in FreeBSD 10.0 using sssd with the AD backend with Kerberos TGT working?
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Demoted domain controller still authenticating users
Why is a demoted domain controller still authenticating users?
Whenever users log onto workstations with domain accounts, this demoted DC authenticates them. Its security log shows their logons, ...
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Kerberos authentication, service host and access to KDC
I have a web application (hostname: service.domain.com) and I wish to use Kerberos authentication to identify users that are logged into a Windows domain. Microsoft AD (Windows Server 2008 R2) is ...
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How to deny access to disabled AD accounts via kerberos in pam_krb5?
I have a working AD/Linux/LDAP/KRB5 directory and authentication setup, with one small problem. When an account is disabled, SSH publickey authentication still allows user login.
It's clear that ...
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Is this Kerberos/AD setup possible?
We have a slightly complicated IDAM setup:
I.e. the end user's machine and browser sit in one network with the parent AD, and our Jetty-based application and the AD that it can talk to (local AD) sit ...
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Change local password as root after configuring for MS-AD Kerberos+LDAP
I have followed this excellent post to configure Kerberos + LDAP:
http://koo.fi/blog/2013/01/06/ubuntu-12-04-active-directory-authentication/
However, there are some local users used for services.
...
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0x19 KDC_ERR_PREAUTH_REQUIRED in my event log
So I have a server, and every time a user or service account logs on to the machine, an error event is generated in the System log:
A Kerberos Error Message was received:
on logon session DOMAIN\...
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Add new server to Server Manager, get Kerberos error 0x80090322
I'm setting up a Windows lab environment. It has a Win2012R2 domain controller (srv001) and I'd like to add another Win2012R2 server to the domain (srv003). Actually, all goes well. I gave the new ...
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How to Change the Kerberos Default Ticket Lifetime
Our KDC servers are running either Ubuntu Dapper (2.6.15-28) or Hardy (2.6.24-19). The Kerberos software is the MIT implementation of Kerberos 5. By default, a Kerberos ticket lasts for 10 hours. ...
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Possible to authenticate Samba via Kerberos but without domain-join?
With a Kerberos config file...
[realms]
DOMAIN.COM = {
kdc = dc1.domain.com
admin_server = dc1.domain.com
}
...it is possible for Linux to talk to Active Directory for password ...
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How to remotely generate Windows AD Kerberos keytab from a Unix machine?
I would like to know if it’s possible to create a keytab file direct from a client machine without using the ktpass utility in the Windows Server side.
The main reason I would want this, is to ...
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Kerberos: Separating AS and TGS
In Kerberos, the Authentication Server (AS) and the Ticket Granting Server (TGS) are generally implemented on the same server. This machine is called the Key Distribution Center (KDC).
Surely, it ...
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Any options out there for kerberized ssh client on windows?
Are there any good (reliable / free) ssh clients that work easily with Active Directory authenticated accounts in a Windows environment? Ideally that wouldn't need the Kerberos for Windows package?
...
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Running a Windows service under a domain user account
If I run a Windows service on some host under a domain user account, and the password for this account changes at some later point, will the service now fail to start, until you update the password?
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Unable to setup Kerberos on Ubuntu 14.04 - krb5kdc: No such file or directory - while initializing database for realm myrealm
I'm attempting to follow the guide on the Ubuntu wiki for installing and setting up Kerberos. I am running Ubuntu 14.04 (LTS) 64-bit. I have setup avahi-daemon in order to provide .local DNS names. I ...
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"setspn -s" vs. "setspn -a"
According to the Setspn Overview, it's discouraged to use Setspn -A to add an SPN record and it's suggested to use Setspn -S instead.
It's said that Setspn -S checks if SPN already exists before ...
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Can Windows integrate with LDAP?
Given an existing LDAP server used for authentication, can Windows desktops authenticate users against LDAP or perhaps Kerberos?
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Changing login-formats for Linux and Active Directory
On CentOS, I run realm list and see login-formats: %[email protected]
I'd like to change login-formats: %[email protected] to login-formats: %U
How would I go about doing this? I'm assuming there is a ...