From 467ffb6478d89839490446e6c0a95f24cedd9893 Mon Sep 17 00:00:00 2001
From: aishwaryabk <58809482+aishwaryabk@users.noreply.github.com>
Date: Wed, 22 Sep 2021 13:09:48 +0530
Subject: [PATCH] Add RHCOS kernel options before installation (#129)

Signed-off-by: Aishwarya Kamat <aishwarya.kamat@ibm.com>
---
 README.md                                     |  1 +
 examples/install_vars.yaml                    |  2 ++
 playbooks/roles/ocp-config/README.md          | 35 ++++++++++---------
 .../roles/ocp-config/defaults/main/main.yaml  |  1 +
 playbooks/roles/ocp-config/tasks/main.yaml    |  6 +++-
 .../ocp-config/tasks/preinstall-kernel.yaml   |  9 +++++
 .../templates/preinstall-node-kargs.yaml.j2   | 11 ++++++
 7 files changed, 47 insertions(+), 18 deletions(-)
 create mode 100644 playbooks/roles/ocp-config/tasks/preinstall-kernel.yaml
 create mode 100644 playbooks/roles/ocp-config/templates/preinstall-node-kargs.yaml.j2

diff --git a/README.md b/README.md
index 20d9c8ed..20b2ef80 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,7 @@ workdir: <Directory to use for creating OCP configs>
 storage_type: <Storage type used in the cluster. Eg: nfs (Note: Currently NFS provisioner is not configured using this playbook. This variable is only used for setting up image registry to EmptyDir if storage_type is not nfs)>
 log_level: <Option --log-level in openshift-install commands. Default is 'info'>
 release_image_override: '<This is set to OPENSHIFT_INSTALL_RELEASE_IMAGE_OVERRIDE while creating ign files. If you are using internal artifactory then ensure that you have added auth key to the pull_secret>'
+rhcos_pre_kernel_options: <List of day-1 kernel options for RHCOS nodes eg: ["rd.multipath=default","root=/dev/disk/by-label/dm-mpath-root"]>
 rhcos_kernel_options: <List of kernel options for RHCOS nodes eg: ["slub_max_order=0","loglevel=7"]>
 ```
 
diff --git a/examples/install_vars.yaml b/examples/install_vars.yaml
index c885d6f7..0c928ce8 100644
--- a/examples/install_vars.yaml
+++ b/examples/install_vars.yaml
@@ -12,6 +12,8 @@ release_image_override: ""
 
 node_connection_timeout: 2700
 
+rhcos_pre_kernel_options: []
+
 rhcos_kernel_options: []
 
 setup_squid_proxy: false
diff --git a/playbooks/roles/ocp-config/README.md b/playbooks/roles/ocp-config/README.md
index 6eafb6e9..bd000b42 100644
--- a/playbooks/roles/ocp-config/README.md
+++ b/playbooks/roles/ocp-config/README.md
@@ -15,23 +15,24 @@ Requirements
 Role Variables
 --------------
 
-| Variable                | Required | Default        | Comments                                    |
-|-------------------------|----------|----------------|---------------------------------------------|
-| workdir                 | no       | ~/ocp4-workdir | Place for config generation and auth files  |
-| log_level               | no       | info           | Option --log-level in openshift-install cmd |
-| release_image_override  | no       | ""             | OCP image overide variable                  |
-| master_count            | yes      |                | Number of master nodes                      |
-| worker_count            | yes      |                | Number of worker nodes                      |
-| setup_squid_proxy       | no       | false          | Flag for setting up squid proxy server on bastion node |
-| proxy_url               | no       | ""             | Proxy url eg: http://[user:passwd@]server:port (NA when setup_squid_proxy: true)|
-| no_proxy                | no       | ""             | Comma seperated string of domains/cidr to exclude proxy |
-| enable_local_registry   | no       | false          | Set to true to enable usage of local registry for restricted network install |
-| chronyconfig.enabled    | no       | true           | Set to true to enable chrony configuration on the bastion node during installation. This also configure the bastion as a NTP server for the cluster. |
-| chronyconfig.content    | no       | ""             | List of time NTP servers and options pair (see chronyconfig examples). If empty, bastion will try sync with some default ntp server (internet) AND local HW clock (with higher stratum). |
-| chronyconfig.allow      | no       | ""             | List of network cidr (X.X.X.X/Y) allowed to sync with bastion configured as NTP server |
-| dhcp_shared_network     | no       |                | Flag to update DHCP server work on a shared network. (Neither ACK nor NACK unknown clients) |
-| cni_network_provider    | no       | OpenshiftSDN   | Sets the default Container Network Interface (CNI) network provider for the cluster |
-| cni_network_mtu         | no       |                | MTU value to assign to the CNI network. Recommended values for OpenshiftSDN: <NIC MTU> - 50; OVNKubernetes: <NIC MTU> - 100 |
+| Variable                    | Required | Default        | Comments                                    |
+|-----------------------------|----------|----------------|---------------------------------------------|
+| workdir                     | no       | ~/ocp4-workdir | Place for config generation and auth files  |
+| log_level                   | no       | info           | Option --log-level in openshift-install cmd |
+| release_image_override      | no       | ""             | OCP image overide variable                  |
+| master_count                | yes      |                | Number of master nodes                      |
+| worker_count                | yes      |                | Number of worker nodes                      |
+| setup_squid_proxy           | no       | false          | Flag for setting up squid proxy server on bastion node |
+| proxy_url                   | no       | ""             | Proxy url eg: http://[user:passwd@]server:port (NA when setup_squid_proxy: true)|
+| no_proxy                    | no       | ""             | Comma seperated string of domains/cidr to exclude proxy |
+| enable_local_registry       | no       | false          | Set to true to enable usage of local registry for restricted network install |
+| chronyconfig.enabled        | no       | true           | Set to true to enable chrony configuration on the bastion node during installation. This also configure the bastion as a NTP server for the cluster. |
+| chronyconfig.content        | no       | ""             | List of time NTP servers and options pair (see chronyconfig examples). If empty, bastion will try sync with some default ntp server (internet) AND local HW clock (with higher stratum). |
+| chronyconfig.allow          | no       | ""             | List of network cidr (X.X.X.X/Y) allowed to sync with bastion configured as NTP server |
+| dhcp_shared_network         | no       |                | Flag to update DHCP server work on a shared network. (Neither ACK nor NACK unknown clients) |
+| cni_network_provider        | no       | OpenshiftSDN   | Sets the default Container Network Interface (CNI) network provider for the cluster |
+| cni_network_mtu             | no       |                | MTU value to assign to the CNI network. Recommended values for OpenshiftSDN: <NIC MTU> - 50; OVNKubernetes: <NIC MTU> - 100 |
+| rhcos_pre_kernel_options    | no       | []             | List of day-1 kernel options for RHCOS nodes eg: ["rd.multipath=default","root=/dev/disk/by-label/dm-mpath-root"] |
 
 *chronyconfig variable example *
 
diff --git a/playbooks/roles/ocp-config/defaults/main/main.yaml b/playbooks/roles/ocp-config/defaults/main/main.yaml
index 151b86bf..a627959a 100644
--- a/playbooks/roles/ocp-config/defaults/main/main.yaml
+++ b/playbooks/roles/ocp-config/defaults/main/main.yaml
@@ -2,6 +2,7 @@
 # defaults file
 
 workdir: ~/ocp4-workdir
+rhcos_pre_kernel_options: []
 log_level: info
 release_image_override: ""
 proxy_url: ""
diff --git a/playbooks/roles/ocp-config/tasks/main.yaml b/playbooks/roles/ocp-config/tasks/main.yaml
index 37a261d6..f4b3bbae 100644
--- a/playbooks/roles/ocp-config/tasks/main.yaml
+++ b/playbooks/roles/ocp-config/tasks/main.yaml
@@ -59,7 +59,11 @@
       src: ../templates/cluster-network-03-config.yml.j2
       dest: "{{ workdir }}/manifests/cluster-network-03-config.yml"
     when: cni_network_mtu is defined
-
+ 
+  - name: Configure RHCOS kernel options via MachineConfig before installation
+    when: rhcos_pre_kernel_options | length > 0
+    import_tasks: preinstall-kernel.yaml
+  
   - name: Remove the machine yaml files
     file:
       path: "{{ item }}"
diff --git a/playbooks/roles/ocp-config/tasks/preinstall-kernel.yaml b/playbooks/roles/ocp-config/tasks/preinstall-kernel.yaml
new file mode 100644
index 00000000..998d13f7
--- /dev/null
+++ b/playbooks/roles/ocp-config/tasks/preinstall-kernel.yaml
@@ -0,0 +1,9 @@
+- name: Create kernel arguments
+  vars:
+    role_n: '{{ item }}'
+  template:
+    src: preinstall-node-kargs.yaml.j2
+    dest: "{{ workdir }}/manifests/preinstall-{{ item }}-kargs.yaml"
+  with_items:
+    - master
+    - worker
diff --git a/playbooks/roles/ocp-config/templates/preinstall-node-kargs.yaml.j2 b/playbooks/roles/ocp-config/templates/preinstall-node-kargs.yaml.j2
new file mode 100644
index 00000000..638e7972
--- /dev/null
+++ b/playbooks/roles/ocp-config/templates/preinstall-node-kargs.yaml.j2
@@ -0,0 +1,11 @@
+apiVersion: machineconfiguration.openshift.io/v1
+kind: MachineConfig
+metadata:
+  labels:
+    machineconfiguration.openshift.io/role: '{{ role_n }}'
+  name: 'preinstall-{{ role_n }}-kargs'
+spec:
+  kernelArguments:
+{% for option in rhcos_pre_kernel_options %}
+     - '{{ option }}'
+{% endfor %}