The default installation of FreeIPA includes the Dogtag certificate management system, a Certificate Authority for your network. It manages expiration of certificates and can automatically renew them. Any client machines on your network will trust the services you provide (you may need to import the IPA CA cert).
There are a number of ways to make certificates. You can generate a certificate signing request or you can have Dogtag manage the whole process for you. You can also create individual cert and key files or put them into a nss database. My preferred method is to use individual files and have Dogtag do the work for me.
If you so desire, you can join your servers to the realm in just the same manner as a desktop client. However, even if they are not joined to the realm you can still create certs for them! You will need to run a few additional steps though, namely creating DNS records and adding the machine manually.
Let’s create a certificate for a web server on www.test.lan (192.168.0.100) which is has not joined our realm.
SSH onto your IPA server and get a kerberos ticket.
[user@machine ~]# ssh email@example.com
[root@ipa-server ~]# kinit admin
If the host is not already in the realm, create DNS entries and add the host.
[root@ipa-server ~]# ipa dnsrecord-add test.lan www --a-rec 192.168.0.100
[root@ipa-server ~]# ipa dnsrecord-add 0.168.192.in-addr.arpa. 100 --ptr-rec www.test.lan.
[root@ipa-server ~]# ipa host-add www.test.lan
Add a web service for the www machine.
[root@ipa-server ~]# ipa service-add HTTP/www.test.lan
Only the target machine can create a certificate (IPA uses the host kerberos ticket) by default, so to be able to create the certificate on your IPA server you need to allow it to manage the web service for the www host.
[root@ipa-server ~]# ipa service-add-host --hosts=ipa-server.test.lan HTTP/www.test.lan
Now create the cert and key.
[root@ipa-server ~]# ipa-getcert request -r -f /etc/pki/tls/certs/www.test.lan.crt -k
/etc/pki/tls/private/www.test.lan.key -N CN=www.test.lan -D
www.test.lan -K HTTP/www.test.lan
Now copy that key and certificate to your web server host and configure apache as required.
[root@ipa-server ~]# rsync -P /etc/pki/tls/certs/www.test.lan.crt /etc/pki/tls/private/www.test.lan.key firstname.lastname@example.org:
You can also easily delete keys so that they aren’t tracked and renewed any more, first get the request id.
[root@ipa-server ~]# ipa-getcert list
Take note of the id for the certificate you want to delete.
[root@ipa-server ~]# getcert stop-tracking -i [request id]
A CRL (certificate revocation list) is automatically maintained and published on the IPA server at https://ipa-server.test.lan/ipa/crl/MasterCRL.bin