Carbonio Mesh Credentials

The credentials used by Carbonio Mesh are stored in file /etc/zextras/service-discover/cluster-credentials.tar.gpg, which is a tar archive that has been encrypted with GPG. The tar archive contains:

  • The bootstrap token

  • The Carbonio Mesh internal CA and its corresponding private key

  • The encryption keys

Warning

If the file /etc/zextras/service-discover/cluster-credentials.tar.gpg becomes compromised, the security of the whole infrastructure will be compromised as well.

The file with the Carbonio Mesh credentials must be present and accessible during various administration activities: Carbonio setup and upgrade, when running pending-setups, and while carrying out other minor tasks that involve Carbonio components.

The file mentioned above is GPG-encrypted using a secret (which is nothing more than another password), that is stored in /var/lib/service-discover/password and is accessible only by the root user. The secret is needed when running the pending-setups command and during the Service Discover installation wizard.

Hence, if you do not remember the password, log in as root to your Single-Server Carbonio, while if you are on a Multi-Server, log in to any Carbonio Mesh Server, then read the /var/lib/service-discover/password file.

In case you want to change the secret, or you need to change it (for example because it has been compromised, shared with or sent to the wrong persons, or if one of the system administrators has left your company), it is necessary to Regenerate Carbonio Mesh Secret.

Regenerate Carbonio Mesh Secret

In case the secret needs to be changed, there is one important information to know beforehand: the reset index value, which is always an integer.

Retrieve the reset index

Simply execute the command

# consul acl bootstrap

The output will always be similar to:

Failed ACL bootstrapping: Unexpected response code: 403 (Permission denied: ACL bootstrap no longer allowed (reset index: 908))

The reset index value* is the last bit of the output (reset index: 908): in our case 908, which is the current index and is needed in the procedure below.

Before attempting the recover, be prepared for a downtime of the Carbonio Mesh service for the whole duration of the procedure.

The procedure is the same for Single-Server and Multi-Server, but on the Multi-Server there are a few more steps to carry out.

Preliminary Tasks

In case of a Single-Server node, log in to it and skip to Step 1 below.

On a Multi-Server, you need to identify the Carbonio Mesh leader node node and log into it. Most of the times, this is the Directory-Server node, whose IP address is retrieved using the command below.

# carbonio prov gas service-discover

To make sure you are on the leader, use the following command.

# wget http://127.0.0.1:8500/v1/status/leader -qO -

The output will be an IP address and a port, for example 192.168.56.101:8300. If this IP is different from the Directory Server’s, log in to the latter on (192.168.56.101).

Note

All the commands must be run on the leader node, unless differently specified.

Step 1. Wipe Old Credentials

The first task, to be executed as the service-discover user, is to write the current reset index to a file, to allow a new ACL token to be generated. As described in the Scenario above, the value is 908 (change it according to the output you receive), so we need to execute:

# sudo -u service-discover bash -c "echo 908 > /var/lib/service-discover/data/acl-bootstrap-reset"

Then stop the service-discover service.

# systemctl stop service-discover

Remove the following two files:

# rm /etc/zextras/service-discover/config.json
# rm /etc/zextras/service-discover/main.json

Finally, remove all certificates related to service-discover.

# rm /var/lib/service-discover/*.pem

Step 2. Generate New Credentials

Run the setup as a first instance.

# service-discover setup 192.168.56.101 --first-instance --password=MESH_SECRET

This is essentially the same command as the one used during the configuration of Carbonio Mesh, the only difference being that in this case we use the explicit IP address and run it as first instance.

Optionally, verify the ACL token using the commands

# export CONSUL_HTTP_TOKEN=$(gpg -qdo - /etc/zextras/service-discover/cluster-credentials.tar.gpg | tar xOf - consul-acl-secret.json | jq .SecretID -r)
# consul members
  Node              Address              Status  Type    Build  Protocol  DC   Segment
  mail.example.com  192.168.56.101:8301  alive   server  1.9.3  2

On a Single-Server the procedure has been completed. Make sure to store the new credentials in a safe place!

Multi-Server Final Task

On a Multi-Server, you need to copy the credentials file on all other nodes, for example using scp. The commands to be used are mentioned in every node of the Multi-Server Installation.

Finally, log in to all other nodes and repeat on each of them the setup using the following commands

# rm /var/lib/service-discover/*pem
# service-discover setup $(hostname -i) --password=MESH_SECRET