Scale

The Vault charm uses the raft backend to scale. This guide walks you through scaling Vault.

Pre-requisites

• Vault is initialised and unsealed
• The Vault charm is authorised

1. Validate that Vault is an active state

Run juju status:

Model  Controller          Cloud/Region        Version  SLA          Timestamp
demo   microk8s-localhost  microk8s/localhost  3.4.0    unsupported  12:52:32-04:00

App    Version  Status   Scale  Charm      Channel    Rev  Address         Exposed  Message
vault           waiting      1  vault-k8s  1.15/beta  198  10.152.183.208  no       installing agent

Unit      Workload  Agent  Address      Ports  Message
vault/0*  active    idle   10.1.182.38

2. Scale Vault to 3 units

Add 2 more units:

juju add-unit vault -n 2

The new units will be sealed:

Model  Controller          Cloud/Region        Version  SLA          Timestamp
demo   microk8s-localhost  microk8s/localhost  3.4.0    unsupported  12:54:51-04:00

App    Version  Status   Scale  Charm      Channel    Rev  Address         Exposed  Message
vault           waiting      3  vault-k8s  1.15/beta  198  10.152.183.208  no       installing agent

Unit      Workload  Agent  Address      Ports  Message
vault/0*  active    idle   10.1.182.38         
vault/1   blocked   idle   10.1.182.51         Please unseal Vault
vault/2   blocked   idle   10.1.182.34         Please unseal Vault

Set the VAULT_ADDR variable to the vault/1 unit:

export VAULT_ADDR=https://$(juju status vault/1 --format=yaml |  yq '.applications.vault.units.vault/1.address'):8200; echo $VAULT_ADDR

Set the VAULT_SKIP_VERIFY to true:

export VAULT_SKIP_VERIFY=true

Unseal the the vault/1 unit using the same unseal keys as received during the initialization of the Vault leader:

vault operator unseal EJoB62t286mjUpSQYZg3mOla3lz/bbElVL5OLnj+rpE=

And complete the same operations for the vault/2 unit:

export VAULT_ADDR=https://$(juju status vault/2 --format=yaml |  yq '.applications.vault.units.vault/2.address'):8200; echo $VAULT_ADDR
vault operator unseal EJoB62t286mjUpSQYZg3mOla3lz/bbElVL5OLnj+rpE=

3. Validate that all units are part of the cluster

All units should go to the Active/Idle Juju status:

$ juju status
Model  Controller          Cloud/Region        Version  SLA          Timestamp
demo   microk8s-localhost  microk8s/localhost  3.4.0    unsupported  12:57:52-04:00

App    Version  Status  Scale  Charm      Channel    Rev  Address         Exposed  Message
vault           active      3  vault-k8s  1.15/beta  198  10.152.183.208  no       

Unit      Workload  Agent  Address      Ports  Message
vault/0*  active    idle   10.1.182.38         
vault/1   active    idle   10.1.182.51         
vault/2   active    idle   10.1.182.34 

And they should all be part of the raft cluster:

$ vault operator raft list-peers
Node            Address                                                State       Voter
----            -------                                                -----       -----
demo-vault/0    vault-0.vault-endpoints.demo.svc.cluster.local:8201    leader      true
demo-vault/1    vault-1.vault-endpoints.demo.svc.cluster.local:8201    follower    true
demo-vault/2    vault-2.vault-endpoints.demo.svc.cluster.local:8201    follower    true