Thanks for that. From what I've read there is no simple right answer. In 2013 
RedHat itself says to leave ChallengeResponseAuthentication set to no "due to 
security reasons".

https://access.redhat.com/solutions/336773

Setting PasswordAuthentication yes seems to leave all the other settings within 
thee sshd_config file like "PermitRootLogin without-password" which may be 
overridden elsewhere if ChallengeResponseAuthentication is set to yes

Terry

-----Original Message-----
From: Simo Sorce [mailto:s...@redhat.com] 
Sent: 25 February 2016 15:01
To: Terry John
Cc: freeipa-users@redhat.com
Subject: Re: [Freeipa-users] 14: No supported authentication methods available

On Thu, 2016-02-25 at 14:36 +0000, Terry John wrote:
> This turned out to be a setting in /etc/ssh/sshd_config which gets 
> overridden by ipa-client-install. Needed to un-comment
> 
> PasswordAuthentication yes

This is disabled because we enable ChallengeResponseAuthentication which is a 
superset of PasswordAuthentication.

PasswordAuthentication can't deal with PAM prompts, it is a oneshot only option 
(ie fails if PAM asks you to make a pasword change), while 
ChallengeResponseAuthentication is the more modern method that properly deals 
with PAM prompts.

You should prefer ChallengeResponseAuthentication over PasswordAuthentication.

HTH,
Simo.


> Terry
> 
> From: freeipa-users-boun...@redhat.com 
> [mailto:freeipa-users-boun...@redhat.com] On Behalf Of Terry John
> Sent: 18 February 2016 11:41
> To: freeipa-users@redhat.com
> Subject: [Freeipa-users] 14: No supported authentication methods 
> available
> 
> I have an AWS instance running Centos 6.7 correctly configured for freeipa 
> but I needed to make a backup machine which would remain live.
> 
> I created a clone of the machine and changed the host name and the settings 
> in /etc/hosts. When I tried to run ipa-client-install it told me to run the 
> uninstall which I did. This had the worrying effect of not being able to log 
> into my original live server but thankfully after a while it came good. I 
> don't know why.
> 
> Back on the new server I ran 'ipa-client-install --enable-dns-updates 
> -mkhomedir' and it seemed to run ok. The host was created on the freeipa GUI 
> and I added it to the same host group as the original server. But when I try 
> to log in via SSH I get the error 'No supported authentication methods 
> available'. I do have root access via the AWS Key file.
> 
> As far as I can tell all the relevant settings seem the same between the two 
> servers but one works and the other doesn't. I can kinit and klist using my 
> freeipa account. 'getent netgroup my-servergroup' works fine.
> 
> I can't seem to find anything relevant in the sssd logs and 
> /var/log/secure just give me the same error of no supported 
> authentication methods available
> 
> I have noticed in /var/log/messages when I restart sssd and error 
> which may be relevant but can't find anything useful so far
> 
> sssd[be[my.domain.net]]: dereference processing failed : Input/output 
> error
> 
> Thanks
> 
> Terry
> 
> 
> 
> The Manheim group of companies within the UK comprises: Manheim Europe 
> Limited (registered number: 03183918), Manheim Auctions Limited (registered 
> number: 00448761), Manheim Retail Services Limited (registered number: 
> 02838588), Motors.co.uk Limited (registered number: 05975777), Real Time 
> Communications Limited (registered number: 04277845) and Complete Automotive 
> Solutions Limited (registered number: 05302535). Each of these companies is 
> registered in England and Wales with the registered office address of Central 
> House, Leeds Road, Rothwell, Leeds LS26 0JE. The Manheim group of companies 
> operates under various brand/trading names including Manheim Inspection 
> Services, Manheim Auctions, Manheim Direct, Manheim De-fleet and Manheim 
> Aftersales Solutions.
> 
> V:0CF72C13B2AC
> 
> 
> --
> Manage your subscription for the Freeipa-users mailing list:
> https://www.redhat.com/mailman/listinfo/freeipa-users
> Go to http://freeipa.org for more info on the project


-- 
Simo Sorce * Red Hat, Inc * New York


-- 
Manage your subscription for the Freeipa-users mailing list:
https://www.redhat.com/mailman/listinfo/freeipa-users
Go to http://freeipa.org for more info on the project

Reply via email to