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|description=Replication testing.
|description=Replication testing.
|setup=
|setup=
# You will need at least 2 machines to do replication testing but if you have more that is good too. Start on one server and perform an IPA Installation (see [[QA:Testcase_freeipav3_installation]]). Let's call the first server srv1.
# You will need at least 2 machines to do replication testing but if you have more that is good too. Start on one server and perform an IPA Installation (see [[QA:Testcase_freeipa_trust_server_installation]]). Let's assume that first server was named srv1 (srv1.ipa.example.org), and we will deploy a replica named srv2 (srv2.ipa.example.org).
 
|actions=
|actions=
=== First Replica ===
# If the first server is acting as the DNS server for the domain, configure the replica system to use it as its DNS server for now
 
# Install the FreeIPA server package group: {{command|dnf -y groupinstall freeipa-server}}
Creating a replica is a two-step process. A file representing the replica is prepared on an existing IPA server and this file is then used to install on a new replica.
# Enrol the system as a replica, interactively:
 
#: {{command|ipa-replica-install [--setup-dns]}}
==== Prepare a Replica ====
#: or with all options on the command line:
 
#: {{command|ipa-replica-install [--setup-dns] [--setup-ca] [--server srv1.ipa.example.org] -U --principal admin --admin-password password}}
Let's create a replica named srv2
#: It's probably best to enable DNS if the first server had it enabled, and to enable CA support so that this server can operate independently of the first server if it goes down. {{code|--server}} should not be needed if the first server is acting as a DNS server.
 
# Verify entries created on srv1 are available on srv2:
On srv1 run as root:
#: {{command|kinit admin}}
 
#: {{command|ipa user-show admin}}
# ipa-replica-prepare srv2.ipa.example.org
#: {{command|id admin}}
 
#: {{command|getent passwd admin}}
NOTE: if you installed ipa1 with the --setup-dns option you can create DNS records on the fly with the following command:
# Now try the reverse - add some entries on srv2 and they should show up on srv1:
 
#: {{command|1=ipa user-add --first=Glen --last=Jones gjones}}
# ipa-replica-prepare --ip-address=10.1.2.1 srv2.ipa.example.org
#: {{command|1=ipa group-add --desc='Office assistants' assistants}}
 
# On srv1 run:
Copy the resulting file to srv2:
#: {{command|ipa user-show gjones}}
 
#: {{command|ipa group-show assistants}}
# scp /var/lib/ipa/replica-info-srv2.ipa.example.org.gpg srv2.ipa.example.org:
# To open all firewall ports typically required for FreeIPA using firewalld, run these commands:
 
#: {{command|for i in freeipa-ldap freeipa-ldaps dns; do firewall-cmd --permanent --add-service $i; done}}
Create a couple of entries on the existing IPA server:
#: {{command|systemctl restart firewalld.service}}
 
# If you have extra test systems available, you can now test installing clients via [[QA:Testcase_realmd_join_sssd|the realm CLI]], [[QA:Testcase_realmd_join_kickstart|kickstart]] and/or [[QA:Testcase realmd join cockpit|cockpit]]. Test enrolling clients against both servers, and verify they work as expected whether both servers are up or either one is down. You may also go on to test more advanced replication features in [[QA:Testcase freeipa replication advanced]].
# kinit admin
# ipa user-add psmith --first=Patty --last=Smith
# ipa group-add engineering --desc=Engineers
 
==== Installing the Replica ====
 
An IPA replica is a full copy of an IPA server. It has the same requirements that any server has, it will just be configured to share data to one or more other IPA servers.
 
NOTE: Make sure iptables is properly configured on all ipa servers or turn it off for testing:
 
Start by installing the FreeIPA packages.
 
On srv2 as root:
 
# yum install freeipa-server
 
# ipa-replica-install /root/replica-info-srv2.ipa.example.org.gpg
 
The installation should exit gracefully with no errors.
 
==== Verifying the Installation ====
 
We added a couple of entries before we installed the replica, verify that they are available on srv2:
 
# kinit admin
# ipa user-show psmith
# ipa group-show engineering
# ipa host-show panther  # should give a "not found" message
 
Now we try the reverse and add some entries on srv2 and they should show up on srv1:
 
# ipa user-add --first=Glen --last=Jones gjones
# ipa group-add --desc='Office assistants' assistants
 
On srv1 run:
 
# ipa user-show gjones
# ipa group-show assistants
 
==== CA Replica ====
 
By default, a certificate authority is not installed on replicas. To add it to srv2, run:
 
# ipa-ca-install /root/replica-info-srv2.ipa.example.org.gpg
 
The installation should exit gracefully with no errors.
 
=== Second Replica ===
 
If you have another machine to test with then continue, otherwise skip to the next set of tests.
 
Let's create a third server named srv3.
 
Let's create a replica on srv2 this time. This will result in a replication topology of:
 
srv1 <-> srv2 <-> srv3
 
Make sure you have installed a certificate authority on srv2. Only masters with a CA can be used to create replicas.
 
On srv2 run:
 
# ipa-replica-prepare srv3.ipa.example.org
# scp /var/lib/ipa/replica-info-srv3.ipa.example.org.gpg srv3.ipa.example.org:
 
On srv3 run:
 
# yum install freeipa-server
 
# ipa-replica-install /root/replica-info-srv3.ipa.example.org.gpg
 
The installation should exit gracefully with no errors.
 
The same steps in '''Verifying the Installation''' should pass.
 
Entries added on srv3 should appear on both srv2 and srv1.
 
=== Management Tools ===
 
When there are more than 2 replicas, it is possible to play with the topology.
 
==== Testing replication failures ====
 
After we created the 2 replicas we are left with a replication topology where srv1 and srv3 both replicate with srv2 but they do not replicate with each other. This means that if srv2 is shut down the other 2 replicas become isolated.
 
 
Go on srv2 and shut down ipa:
 
# ipactl stop
 
 
Now go on srv1 and create a new user:
 
# ipa user-add --first=John --last=Doe jdoe
 
Switch to srv3 and check that jdoe has not been replicated yet.
 
# ipa user-show jdoe
ipa: ERROR: jdoe: user not found
 
Go to srv2 and restart ipa:
 
# ipactl start
 
Verify that after a ipa is fully started on srv2 that the jdoe user is available:
 
# ipa user-show jdoe
 
Do the same on srv3 to verify that replication has been restored and all servers are now synchronized.
 
==== Listing servers and replication agreements ====
 
You can list all replicating servers in your domain with:
 
# ipa-replica-manage list
srv1.ipa.example.org
srv2.ipa.example.org
srv3.ipa.example.org
 
If you want to check which are the replication peers of srv2:
 
# ipa-replica-manage list srv2.ipa.example.org
srv1.ipa.example.org
srv3.ipa.example.org
 
For srv1 and srv3 you should get only srv3 and srv1 respectively.
 
Use --verbose when asking about a specific server to get more information about its peers.
 
==== Changing Topology ====
 
To avoid the split brain situation above let's play with topology and add a new link between srv1 and srv3 so that if srv2 is down, the other 2 keeps replicating.
 
On srv1 issue the following command:
 
# ipa-replica-manage connect srv1.ipa.example.org srv3.ipa.example.org
 
If you have an admin credential cache this command should complete successfully without asking you anything. If you do not have any credentials it will ask you the Directory Manager password.
 
Once this command completes srv1 and srv3 are linked and replicate to each other.
 
Try the tests of the previous section, using a new user name and shutting down again srv2.
After this new link is created the user should be replicated between srv1 and srv3 even when srv2 is down.
 
Now let's break a replication agreement so that srv2 and srv3 do not replicate directly anymore. On srv2 do:
 
# ipa-replica-manage disconnect srv2.ipa.example.org srv3.ipa.example.org
 
Once this is done the replication topolgy should be: srv2 <=> srv1 <=> srv3
Try the tests of the previous section, but turning off srv1 instead.
changes done on srv2 should not be visible in srv3 until you bring up srv1 again.
 
==== Forcing a synchronization and re-initializing replicas ====
 
Replication can take from a few seconds to a few minutes to complete depending on various factors.
 
Try forcing an immediate synchronization by issuing a force-sync command on the replica you want to synchronize.
 
For example to force-sync srv1 from srv2 use this on the srv1 server.
 
# ipa-replica-manage force-sync --from srv2.ipa.example,org
 
NOTE: This commands accepts on a --from parameter, but not a --to, so it must to be run on the replica that needs to be synchronized.
 
It may happen that due to compounding issues, replication can't be easily fixed by a simple re-synchronization. In this case a full re-initialization can be performed:
 
# ipa-replica-manage re-initialize --from srv2.ipa.example.org
 
This command will wipe clean the directory and re-download all the data from srv2.
Ant changes to the local tree that were not replicated are lost.
 
==== Testing clients ====
 
If you have extra machines, install clients on them (see [[QA:Testcase_freeipav3_installation#Add_a_client]]).
The client tests should succeed regardless of which replica is used as the client's master.
 
==== Disposing of a replica ====
 
If a replica becomes useless it should be first removed from the topology with the following command:
 
# ipa-replica-manage del srv3.ipa.example.org
 
In case the machine/vm was destroyed before this command is run use the --force switch in order to remove dangling pointers to the failed replica.
 
The command above does not stop the replica itself.
Once the replica has been removed from the domain, stop it and uninstall it.
 
On srv3:
 
# ipa-server-install --uninstall
 
|results=
|results=
All the test steps should end with the specified results.
# The enrolment should complete successfully with no errors.
# The test commands should show expected output indicating the users and groups are present.
# Client tests should succeed (according to their own expected results) as long as either server is available (assuming appropriate DNS configuration).
}}
}}
[[Category:FreeIPA_Test_Cases]]
[[Category:Server Acceptance Test Cases]]

Latest revision as of 23:03, 3 August 2018

Description

Replication testing.

Setup

  1. You will need at least 2 machines to do replication testing but if you have more that is good too. Start on one server and perform an IPA Installation (see QA:Testcase_freeipa_trust_server_installation). Let's assume that first server was named srv1 (srv1.ipa.example.org), and we will deploy a replica named srv2 (srv2.ipa.example.org).

How to test

  1. If the first server is acting as the DNS server for the domain, configure the replica system to use it as its DNS server for now
  2. Install the FreeIPA server package group: dnf -y groupinstall freeipa-server
  3. Enrol the system as a replica, interactively:
    ipa-replica-install [--setup-dns]
    or with all options on the command line:
    ipa-replica-install [--setup-dns] [--setup-ca] [--server srv1.ipa.example.org] -U --principal admin --admin-password password
    It's probably best to enable DNS if the first server had it enabled, and to enable CA support so that this server can operate independently of the first server if it goes down. --server should not be needed if the first server is acting as a DNS server.
  4. Verify entries created on srv1 are available on srv2:
    kinit admin
    ipa user-show admin
    id admin
    getent passwd admin
  5. Now try the reverse - add some entries on srv2 and they should show up on srv1:
    ipa user-add --first=Glen --last=Jones gjones
    ipa group-add --desc='Office assistants' assistants
  6. On srv1 run:
    ipa user-show gjones
    ipa group-show assistants
  7. To open all firewall ports typically required for FreeIPA using firewalld, run these commands:
    for i in freeipa-ldap freeipa-ldaps dns; do firewall-cmd --permanent --add-service $i; done
    systemctl restart firewalld.service
  8. If you have extra test systems available, you can now test installing clients via the realm CLI, kickstart and/or cockpit. Test enrolling clients against both servers, and verify they work as expected whether both servers are up or either one is down. You may also go on to test more advanced replication features in QA:Testcase freeipa replication advanced.

Expected Results

  1. The enrolment should complete successfully with no errors.
  2. The test commands should show expected output indicating the users and groups are present.
  3. Client tests should succeed (according to their own expected results) as long as either server is available (assuming appropriate DNS configuration).