From a10520ccdd2f7edaa187dc8c05e53acd053e1ff7 Mon Sep 17 00:00:00 2001
From: Rafael Fonseca <r4f4rfs@gmail.com>
Date: Wed, 11 Dec 2024 12:21:24 +0100
Subject: [PATCH] OCPBUGS-43625: azure: use separate /var to avoid growfs
 timeouts

Using the workaround of a separate /var partition until the issue is
fixed in RHCOS.
---
 pkg/asset/ignition/bootstrap/common.go |  7 ++++-
 pkg/asset/ignition/machine/master.go   |  8 +++++
 pkg/asset/ignition/node.go             | 42 ++++++++++++++++++++++++++
 3 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/pkg/asset/ignition/bootstrap/common.go b/pkg/asset/ignition/bootstrap/common.go
index 97db5b7373..025372adf6 100644
--- a/pkg/asset/ignition/bootstrap/common.go
+++ b/pkg/asset/ignition/bootstrap/common.go
@@ -42,6 +42,7 @@ import (
 	"github.com/openshift/installer/pkg/asset/tls"
 	"github.com/openshift/installer/pkg/types"
 	awstypes "github.com/openshift/installer/pkg/types/aws"
+	aztypes "github.com/openshift/installer/pkg/types/azure"
 	baremetaltypes "github.com/openshift/installer/pkg/types/baremetal"
 	gcptypes "github.com/openshift/installer/pkg/types/gcp"
 	nutanixtypes "github.com/openshift/installer/pkg/types/nutanix"
@@ -229,7 +230,8 @@ func (a *Common) generateConfig(dependencies asset.Parents, templateData *bootst
 		}},
 	)
 
-	if platform == nutanixtypes.Name {
+	switch platform {
+	case nutanixtypes.Name:
 		// Inserts the file "/etc/hostname" with the bootstrap machine name to the bootstrap ignition data
 		hostname := fmt.Sprintf("%s-bootstrap", clusterID.InfraID)
 		hostnameFile := igntypes.File{
@@ -245,6 +247,9 @@ func (a *Common) generateConfig(dependencies asset.Parents, templateData *bootst
 			},
 		}
 		a.Config.Storage.Files = append(a.Config.Storage.Files, hostnameFile)
+	case aztypes.Name:
+		// See https://issues.redhat.com/browse/OCPBUGS-43625
+		ignition.AppendVarPartition(a.Config)
 	}
 
 	return nil
diff --git a/pkg/asset/ignition/machine/master.go b/pkg/asset/ignition/machine/master.go
index fca459950a..2e26809716 100644
--- a/pkg/asset/ignition/machine/master.go
+++ b/pkg/asset/ignition/machine/master.go
@@ -7,11 +7,13 @@ import (
 
 	igntypes "github.com/coreos/ignition/v2/config/v3_2/types"
 	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
 
 	"github.com/openshift/installer/pkg/asset"
 	"github.com/openshift/installer/pkg/asset/ignition"
 	"github.com/openshift/installer/pkg/asset/installconfig"
 	"github.com/openshift/installer/pkg/asset/tls"
+	"github.com/openshift/installer/pkg/types/azure"
 )
 
 const (
@@ -42,6 +44,12 @@ func (a *Master) Generate(_ context.Context, dependencies asset.Parents) error {
 
 	a.Config = pointerIgnitionConfig(installConfig.Config, rootCA.Cert(), "master")
 
+	if installConfig.Config.Platform.Name() == azure.Name {
+		logrus.Debugf("Adding /var partition to skip CoreOS growfs step")
+		// See https://issues.redhat.com/browse/OCPBUGS-43625
+		ignition.AppendVarPartition(a.Config)
+	}
+
 	data, err := ignition.Marshal(a.Config)
 	if err != nil {
 		return errors.Wrap(err, "failed to marshal Ignition config")
diff --git a/pkg/asset/ignition/node.go b/pkg/asset/ignition/node.go
index da184a4f14..7b803fa227 100644
--- a/pkg/asset/ignition/node.go
+++ b/pkg/asset/ignition/node.go
@@ -9,6 +9,7 @@ import (
 	igntypes "github.com/coreos/ignition/v2/config/v3_2/types"
 	"github.com/vincent-petithory/dataurl"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/utils/ptr"
 
 	"github.com/openshift/installer/pkg/asset"
 )
@@ -91,3 +92,44 @@ func ConvertToAppendix(file *igntypes.File) {
 	file.Contents = igntypes.Resource{}
 	file.Overwrite = ignutil.BoolToPtr(false)
 }
+
+// AppendVarPartition appends a /var partition to the ignition configuration to avoid growfs.
+func AppendVarPartition(config *igntypes.Config) {
+	// https://docs.openshift.com/container-platform/4.17/installing/installing_platform_agnostic/installing-platform-agnostic.html#installation-user-infra-machines-advanced_vardisk_installing-platform-agnostic
+	config.Storage.Disks = append(config.Storage.Disks, igntypes.Disk{
+		Device: "/dev/disk/by-id/coreos-boot-disk",
+		Partitions: []igntypes.Partition{
+			{
+				Label:    ptr.To("var"),
+				Number:   5,
+				StartMiB: ptr.To(50000),
+				SizeMiB:  ptr.To(0),
+			},
+		},
+	})
+	config.Storage.Filesystems = append(config.Storage.Filesystems, igntypes.Filesystem{
+		Path:         ptr.To("/var"),
+		Device:       "/dev/disk/by-partlabel/var",
+		Format:       ptr.To("xfs"),
+		MountOptions: []igntypes.MountOption{"defaults", "prjquota"},
+	})
+	// generate a mount unit so that this filesystem gets mounted in the real root.
+	config.Systemd.Units = append(config.Systemd.Units, igntypes.Unit{
+		Name:    "var.mount",
+		Enabled: ptr.To(true),
+		Contents: ptr.To(`
+[Unit]
+Requires=systemd-fsck@dev-disk-by\x2dpartlabel-var.service
+After=systemd-fsck@dev-disk-by\x2dpartlabel-var.service
+
+[Mount]
+Where=/var
+What=/dev/disk/by-partlabel/var
+Type=xfs
+Options=defaults,prjquota
+
+[Install]
+RequiredBy=local-fs.target
+`),
+	})
+}