[Freeipa-devel] NTP in FreeIPA

[Rob Crittenden]

David Kupka wrote:
> On 22/11/16 23:15, Gabe Alford wrote:
>> I would say that it is worth keeping in FreeIPA. I know myself and some
>> customers use its functionality by having the clients sync to the IPA
>> servers and have the servers sync to the NTP source. This way if the NTP
>> source ever gets disrupted for long periods of time (which has
>> happened in
>> my environment) the client time drifts with the authentication source.
>> This
>> is the way that AD often works and is configured.
> 
> Hello Gabe,
> I agree that it's common practice to synchronize all nodes in network
> with single source in order to have the same time and save bandwidth.
> Also I understand that it's comfortable to let FreeIPA installer take
> care of it.
> But I don't think FreeIPA should do it IMO this is job for Ansible or
> similar tool. Also the problem is that in some situations FreeIPA
> installer makes it worse.
> 
> Example:
> 
> 1. Install FreeIPA server (ipa1.example.org)
> 2. Install FreeIPA client on all nodes in network
> 3. Install replica (ipa2.example.org) of FreeIPA server to increase
> redundancy
> 
> Now all the clients have ipa1.example.org as the only server in
> /etc/ntp.conf. If the first FreeIPA server becomes unreachable all
> clients will be able to contact KDC on the other server thanks to DNS
> autodiscovery in libkrb5 but will be unable to synchronize time.

Remember that the goal of IPA was to herd together a bunch of software
to make hard things easier. This included dealing with the 5-minute
Kerberos window so ntp was configured on the client and server (which is
less of any issue now).

When making changes you have to ask yourself who are you making this
easier for: you or the user.

Yes, getting NTP right is hard, but does it meet the 80/20 rule in terms
of success? I'd think so. I

If someone wants to configure it using Ansible they can use the
--no-ntp. If they want to use different time servers they can pass in
--ntp-server. But by default IMHO it should do something sane to give a
good experience.

There don't seem to be a ton of NTP tickets and I don't recall a lot of
user's pressing for it to go away (the reverse, many times their
problems revolve around time not being synced). I wonder if a survey on
freeipa-users would be in order to see how hot an issue this really is.

rob