Sarah PETER via FreeIPA-users wrote:
> Dear all,
> 
>  
> 
> TLDR;
> 
> We have an IPA setup consisting of four replicas (2 CA, 2 non-CA)
> without any of the DNS records that ‘ipa dns-update-system-records‘
> suggests and we share our DNS domain with AD. Will we have any issues,
> assuming that we are not using Kerberos automatic discovery, the krb,
> sssd and ipa configuration files have the servers explicitly configured
> and we are not using trust to Active Directory?

We don't typically test this scenario but it should work. You'll be
hardcoding configuration files with specific hosts so failover if a
server is down may not be as robust but it should still work depending
on how you are doing it.

>  
> 
> I have inherited a 10-year-old FreeIPA setup with four replicas, which
> is in a non-supported configuration according to RedHat support, but has
> always worked fine for us. I would like to know if we can keep it
> running like it is, or if we will face issues in the future and if yes,
> which ones.

Do they provide any specific reasons why your configuration is not
supported? Is it this same DNS reason?

>  
> 
> We are a small sub-group in a bigger organization managing our own Linux
> VMs. We manage SSH login with sssd and LDAP logins to web services with
> FreeIPA. Our parent organization runs Active Directory and the DNS
> servers on the same domain that we have configured in FreeIPA. We do not
> have any trust relationship with the Active Directory and won’t ever be
> allowed to have it, either. We do not want any auto-discovery to happen,
> to make sure other people’s machines don’t accidentally try to contact
> or enroll with our infrastructure. Therefore, we have no DNS records at
> all anywhere pointing to our IPA servers and instead always configure
> this explicitly in the client and server install and ipa, sssd and krb
> configuration files.
> 
>  
> 
> We are in the process of migrating to RHEL 8 and the new ipa-healthcheck
> complains on various levels about the missing DNS records (error for
> ipa-ca, warning for the rest). RedHat support insisted that we need to
> migrate our setup to a different domain and create the DNS records.
> However, migration would be a huge challenge, because there is no
> procedure to migrate all data in IPA (we have quite extensive HBAC
> rules) and the DNS records we don’t want to create to prevent
> auto-discovery and also wouldn’t be allowed from the parent organization.

So healthcheck provides recommendations. It isn't the law. If you don't
want DNS you don't have to use it AFAIR, particularly since you don't
use AD. There are downsides but it should still work.

Depending on the RHEL release check the ipahealthcheck.conf(5) man page
for how to exclude certain results. This can make your healthcheck
output end without warning or errors for things you want to ignore.

> 
> I would appreciate if someone could tell me the actual issues that we
> could encounter running this setup with multiple (2 CA, 2 non-CA)
> replicas. I’m mostly concerned about complications with replication or
> certificates (renewal).

Assuming the hosts themselves are in DNS and/or /etc/hosts then
replication should be unaffected. It doesn't rely on discovery.

certificate renewal pretty much the same. Where you may have problems if
you don't have ipa-ca.DOMAIN defined is OCSP and CRL because this is the
name used for that so that the service isn't tied to a specific IPA
host.

We have an ipa to ipa migration tool in upstream that will make
retaining all the records easier. It will still be disruptive because
all the keys will be different so it isn't a panacea.

Your biggest exposure is if an IPA server goes down for an extended
time. Failover may not work as well as it would if you had discovery
enabled.

Ideally in a situation like this your Linux hosts would be in its own
sub-domain that could be delegated to IPA and then it could work in its
own little world. But that is understandably difficult to do after 10 years.

rob

-- 
_______________________________________________
FreeIPA-users mailing list -- freeipa-users@lists.fedorahosted.org
To unsubscribe send an email to freeipa-users-le...@lists.fedorahosted.org
Fedora Code of Conduct: 
https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: 
https://lists.fedorahosted.org/archives/list/freeipa-users@lists.fedorahosted.org
Do not reply to spam, report it: 
https://pagure.io/fedora-infrastructure/new_issue

Reply via email to