Blogs

Add node back into galera cluster (brute force)

admin — Wed, 30 Aug 2023 12:57:41 GMT

Here is the scenario...

You have a 3 node galera (g1,g2,g3) cluster and there is some network maintenance which stops connectivity between the nodes causing them to lose their quorum and stop serving.

To fix this you disable 2 nodes (g2,g3) and bring just one back (g1)...

you should be able to bring the 1 node back with the following command:
galera_new_cluster
If that causes a failure, you may also need to update a line in your /var/lib/mysql/grastate.dat file.
to do this change:
safe_to_bootstrap: 0
to
safe_to_bootstrap: 1
now run the galera_new_cluster command again and it "should" work...

Once your network settles down and connectivity is regained you will have 2 galera nodes which will no longer gracefully start up, what do you do?

Feel free to use the following hammer:

On g2

cd /var/lib/mysql
rm grastate.dat
rm ib_logfile*
sudo -u mysql mysqld --wsrep_sst_donor=g1

where "g1" is the wsrep_node_name of your working/primary galera node

follow the above instructions for g3 and you should be all set...

Jumpcloud SSO (idp) to Keycloak (sp)

admin — Fri, 25 Nov 2022 15:46:28 GMT

Mapping Groups from Jumpcloud

In the above post we set up Jumpcloud SAML SSO auth to use Keycloak as the SP.
In addition, it is sometimes helpful to include your jumpcloud groups in the SAML token. The following instructions should help enable this.

Configure Jumpcloud start by configuring your group to use the SSO App you created for SAML

Screenshot 2022-11-26 at 11.51.30.png

Now update your SAML app to include group information: Go to your SSO App click on the SSO Tab and scroll to the bottom tick the box for Group Attributes give it a name like memberOf (can be any name but you will need this for keycloak) click save

Screenshot 2022-11-26 at 12.00.33.png

Configure Keycloak Open Keycloak admin portal for your realm Click on Roles and create a new role e.g. saml-group

Screenshot 2022-11-26 at 12.04.42.png

Click on Identity Providers and select the provider you created earlier (see above blog post) Click on the Mappers tab Click Create Give it a name e.g. saml-group select Sync Mode Overrride equal to force (this updates the groups associated with this account on every login) Create a new Attributes using the Jumpcloud Group Attributes identifier, in this case memberOf as the key and your Jumpcloud group name as the key Set Regex Attribute Values to On Under Role, choose the role you created

Screenshot 2022-11-26 at 12.11.52.png

Prime Video

admin — Thu, 15 Oct 2020 12:24:50 GMT

heh, we have enough trouble keeping up with Netflix!

What Happened to uNoGS

[[global:guest]] — Wed, 08 Feb 2017 18:14:34 GMT

@admin would an IPv6 only VM work for you? In case I may arrange something