openebs · nicholascioli · Sep 25, 2023
diff --git a/buildscripts/build.sh b/buildscripts/build.sh
@@ -25,9 +25,9 @@
 cd "$DIR"

 # Get the git commit
 if [ -f $GOPATH/src/github.com/openebs/lvm-localpv/GITCOMMIT ];
 then
    GIT_COMMIT="$(cat $GOPATH/src/github.com/openebs/lvm-localpv/GITCOMMIT)"
 else
    GIT_COMMIT="$(git rev-parse HEAD)"
 fi
@@ -38,9 +38,9 @@
 fi

 CURRENT_BRANCH=""
 if [ -z ${BRANCH} ];
 then
  CURRENT_BRANCH=$(git branch | grep \* | cut -d ' ' -f2)
 else
  CURRENT_BRANCH=${BRANCH}
 fi
@@ -49,7 +49,7 @@
 if [ -n "$RELEASE_TAG" ]; then
 	VERSION="$RELEASE_TAG"
 else
 	BUILDDATE=`date +%m-%d-%Y`
 	SHORT_COMMIT="$(git rev-parse --short HEAD)"
 	VERSION="$CURRENT_BRANCH-$SHORT_COMMIT:$BUILDDATE"
 fi
@@ -96,12 +96,13 @@
 if [ $GOOS = "windows" ]; then
     output_name+='.exe'
 fi
-env GOOS=$GOOS GOARCH=$GOARCH go build -ldflags \
+env GOOS=$GOOS GOARCH=$GOARCH CGO_ENABLED=0 go build -ldflags \
     "-X github.com/openebs/lvm-localpv/pkg/version.GitCommit=${GIT_COMMIT} \
     -X main.CtlName='${CTLNAME}' \
     -X github.com/openebs/lvm-localpv/pkg/version.Version=${VERSION} \
     -X github.com/openebs/lvm-localpv/pkg/version.VersionMeta=${VERSION_META}"\
     -o $output_name\
+    -installsuffix cgo \
     ./cmd
 
 echo ""

diff --git a/changelogs/unreleased/164-nicholascioli b/changelogs/unreleased/164-nicholascioli
@@ -0,0 +1 @@
+add support for LVM raid options
diff --git a/ci/ci-test.sh b/ci/ci-test.sh
@@ -33,6 +33,12 @@
 FOREIGN_LVM_SYSTEMID="openebs-ci-test-system"
 FOREIGN_LVM_CONFIG="global{system_id_source=lvmlocal}local{system_id=${FOREIGN_LVM_SYSTEMID}}"
 
+# RAID info for corresponding tests
+RAID_COUNT=5
+
+# RAID info for corresponding tests
+RAID_COUNT=5
+
 # Clean up generated resources for successive tests.
 cleanup_loopdev() {
   sudo losetup -l | grep '(deleted)' | awk '{print $1}' \
@@ -60,13 +66,28 @@
   cleanup_loopdev
 }
 
+cleanup_raidvg() {
+  sudo vgremove raidvg -y || true
+
+  for IMG in `seq ${RAID_COUNT}`
+  do
+    if [ -f /tmp/openebs_ci_raid_disk_${IMG}.img ]
+    then
+      rm /tmp/openebs_ci_raid_disk_${IMG}.img
+    fi
+  done
+
+  cleanup_loopdev
+}
+
 cleanup() {
   set +e
 
   echo "Cleaning up test resources"
 
   cleanup_lvmvg
   cleanup_foreign_lvmvg
+  cleanup_raidvg
 
   kubectl delete pvc -n openebs lvmpv-pvc
   kubectl delete -f "${SNAP_CLASS}"
@@ -93,10 +114,40 @@
 sudo pvcreate "${foreign_disk}"
 sudo vgcreate foreign_lvmvg "${foreign_disk}" --config="${FOREIGN_LVM_CONFIG}"
 
+# setup a RAID volume group
+cleanup_raidvg
+raid_disks=()
+for IMG in `seq ${RAID_COUNT}`
+do
+  truncate -s 1024G /tmp/openebs_ci_raid_disk_${IMG}.img
+  raid_disk="$(sudo losetup -f /tmp/openebs_ci_raid_disk_${IMG}.img --show)"
+  sudo pvcreate "${raid_disk}"
+
+  raid_disks+=("${raid_disk}")
+done
+sudo vgcreate raidvg "${raid_disks[@]}"
+
+# setup a RAID volume group
+cleanup_raidvg
+raid_disks=()
+for IMG in `seq ${RAID_COUNT}`
+do
+  truncate -s 1024G /tmp/openebs_ci_raid_disk_${IMG}.img
+  raid_disk="$(sudo losetup -f /tmp/openebs_ci_raid_disk_${IMG}.img --show)"
+  sudo pvcreate "${raid_disk}"
+
+  raid_disks+=("${raid_disk}")
+done
+sudo vgcreate raidvg "${raid_disks[@]}"
+
 # install snapshot and thin volume module for lvm
 sudo modprobe dm-snapshot
 sudo modprobe dm_thin_pool
 
+# install RAID modules for lvm
+sudo modprobe dm_raid
+sudo modprobe dm_integrity
+
 # Prepare env for running BDD tests
 # Minikube is already running
 kubectl apply -f "${LVM_OPERATOR}"

diff --git a/deploy/lvm-operator.yaml b/deploy/lvm-operator.yaml
@@ -95,12 +95,47 @@ spec:
                 description: Capacity of the volume
                 minLength: 1
                 type: string
+              integrity:
+                description: Integrity specifies whether logical volumes should be
+                  checked for integrity. If it is set to "yes", then the LVM LocalPV
+                  Driver will enable DM integrity for the logical volume
+                enum:
+                - "yes"
+                - "no"
+                type: string
+              lvcreateoptions:
+                description: LvCreateOptions are extra options for creating a volume.
+                  Options should be separated by ; e.g. "--vdo;--readahead;auto"
+                type: string
+              mirrors:
+                description: Mirrors specifies the mirror count for a RAID configuration.
+                minimum: 0
+                type: integer
+              nosync:
+                description: NoSync enables the `--nosync` option of a RAID volume.
+                  If it is set to "yes", then LVM will skip drive sync when creating
+                  the mirrors. Defaults to "no"
+                enum:
+                - "yes"
+                - "no"
+                type: string
               ownerNodeID:
                 description: OwnerNodeID is the Node ID where the volume group is
                   present which is where the volume has been provisioned. OwnerNodeID
                   can not be edited after the volume has been provisioned.
                 minLength: 1
                 type: string
+              raidtype:
+                description: RaidType specifies the type of RAID for the logical volume.
+                  Defaults to linear, if unspecified.
+                enum:
+                - linear
+                - raid0
+                - raid1
+                - raid5
+                - raid6
+                - raid10
+                type: string
               shared:
                 description: Shared specifies whether the volume can be shared among
                   multiple pods. If it is not set to "yes", then the LVM LocalPV Driver
@@ -109,6 +144,18 @@ spec:
                 - "yes"
                 - "no"
                 type: string
+              stripecount:
+                description: StripeCount specifies the stripe count for a RAID configuration.
+                  This is equal to the number of physical volumes to scatter the logical
+                  volume
+                minimum: 0
+                type: integer
+              stripesize:
+                description: StripeSize specifies the size of a stripe for a RAID
+                  configuration. Must be a power of 2 but must not exceed the physical
+                  extent size
+                minimum: 0
+                type: integer
               thinProvision:
                 description: ThinProvision specifies whether logical volumes can be
                   thinly provisioned. If it is set to "yes", then the LVM LocalPV
@@ -129,6 +176,7 @@ spec:
             required:
             - capacity
             - ownerNodeID
+            - raidtype
             - vgPattern
             - volGroup
             type: object

diff --git a/deploy/yamls/lvmvolume-crd.yaml b/deploy/yamls/lvmvolume-crd.yaml
@@ -74,12 +74,47 @@ spec:
                 description: Capacity of the volume
                 minLength: 1
                 type: string
+              integrity:
+                description: Integrity specifies whether logical volumes should be
+                  checked for integrity. If it is set to "yes", then the LVM LocalPV
+                  Driver will enable DM integrity for the logical volume
+                enum:
+                - "yes"
+                - "no"
+                type: string
+              lvcreateoptions:
+                description: LvCreateOptions are extra options for creating a volume.
+                  Options should be separated by ; e.g. "--vdo;--readahead;auto"
+                type: string
+              mirrors:
+                description: Mirrors specifies the mirror count for a RAID configuration.
+                minimum: 0
+                type: integer
+              nosync:
+                description: NoSync enables the `--nosync` option of a RAID volume.
+                  If it is set to "yes", then LVM will skip drive sync when creating
+                  the mirrors. Defaults to "no"
+                enum:
+                - "yes"
+                - "no"
+                type: string
               ownerNodeID:
                 description: OwnerNodeID is the Node ID where the volume group is
                   present which is where the volume has been provisioned. OwnerNodeID
                   can not be edited after the volume has been provisioned.
                 minLength: 1
                 type: string
+              raidtype:
+                description: RaidType specifies the type of RAID for the logical volume.
+                  Defaults to linear, if unspecified.
+                enum:
+                - linear
+                - raid0
+                - raid1
+                - raid5
+                - raid6
+                - raid10
+                type: string
               shared:
                 description: Shared specifies whether the volume can be shared among
                   multiple pods. If it is not set to "yes", then the LVM LocalPV Driver
@@ -88,6 +123,18 @@ spec:
                 - "yes"
                 - "no"
                 type: string
+              stripecount:
+                description: StripeCount specifies the stripe count for a RAID configuration.
+                  This is equal to the number of physical volumes to scatter the logical
+                  volume
+                minimum: 0
+                type: integer
+              stripesize:
+                description: StripeSize specifies the size of a stripe for a RAID
+                  configuration. Must be a power of 2 but must not exceed the physical
+                  extent size
+                minimum: 0
+                type: integer
               thinProvision:
                 description: ThinProvision specifies whether logical volumes can be
                   thinly provisioned. If it is set to "yes", then the LVM LocalPV
@@ -108,6 +155,7 @@ spec:
             required:
             - capacity
             - ownerNodeID
+            - raidtype
             - vgPattern
             - volGroup
             type: object

diff --git a/design/lvm/storageclass-parameters/raid.md b/design/lvm/storageclass-parameters/raid.md
@@ -0,0 +1,129 @@
+---
+title: LVM-LocalPV RAID
+authors:
+  - "@nicholascioli"
+owners: []
+creation-date: 2023-11-04
+last-updated: 2023-11-04
+status: Implemented
+---
+
+# LVM-LocalPV RAID
+
+## Table of Contents
+- [LVM-LocalPV RAID](#lvm-localpv-raid)
+  - [Table of Contents](#table-of-contents)
+  - [Summary](#summary)
+  - [Motivation](#motivation)
+    - [Goals](#goals)
+    - [Non Goals](#non-goals)
+  - [Proposal](#proposal)
+    - [User Stories](#user-stories)
+    - [Implementation Details](#implementation-details)
+    - [Usage details](#usage-details)
+    - [Test Plan](#test-plan)
+  - [Graduation Criteria](#graduation-criteria)
+  - [Drawbacks](#drawbacks)
+  - [Alternatives](#alternatives)
+
+
+## Summary
+
+This proposal charts out the workflow details to support creation of RAID volumes.
+
+## Motivation
+
+### Goals
+
+- Able to provision RAID volumes in a VolumeGroup.
+- Able to specify VolumeGroup-specific RAID options for all sub volumes.
+- Able to specify extra options for all volumes in a VolumeGroup.
+
+### Non Goals
+
+- Validating combinations of RAID types / options.
+
+## Proposal
+
+### User Stories
+
+- RAIDed volumes provide data redundancy and can mitigate data loss due to individual drive failures.
+- Ability to specify extra arguments for VolumeGroups allow for user customizations without needing
+  to rework k8s schemas.
+
+### Implementation Details
+
+- User/Admin has to set RAID-sepcific options under storageclass parameters which
+  are used when creating volumes in the VolumeGroup.
+- During volume provisioning time external-provisioner will read all key-value pairs
+  that are specified under referenced storageclass and pass information to CSI
+  driver as payload for `CreateVolume` gRPC request.
+- After receiving the `CreateVolume` request CSI driver will pick appropriate node based
+  on scheduling attributes(like topology information, matching VG name and available capacity)
+  and creates LVM volume resource by setting `Spec.RaidType` to a valid type along with other properties.
+- Once the LVMVolume resource is created corresponding node LVM volume controller reconcile
+  LVM volume resource in the following way:
+  - LVM controller will check `Spec.RaidType` field, if the field is set to anything other
+    than `linear`, then the controller will perform following operations:
+    - Fetch information about existence of matching VolumeGroup.
+      - If there is a VolumeGroup with <vg_name> name then controller will create a volume.
+        Command used to create thin volume: `lvcreate --type <RAID_TYPE> --raidintegrity <INTEGRITY> --nosync ... <LVCREATEOPTIONS> -y`
+    - If volume creation is successfull then controller will LVM volume resource as `Ready`.
+- After watching `Ready` status CSI driver will return success response to `CreateVolume` gRPC
+  request.
+
+### Usage details
+
+1. User/Admin can configure the following options under the storageclass parameters.
+
+Option | Required | Valid Values | Description
+-------|----------|--------------|-------------------
+`type` | `true` | `raid0` / `stripe`, `raid` / `raid1` / `mirror`, `raid5`, `raid6`, `raid10` | The RAID type of the volume.
+`integrity` | `false` | `true`, `false` | Whether or not to enable DM integrity for the volume. Defaults to `false`.
+`mirrors` | depends | [0, ∞) | Mirror count. Certain RAID configurations require this to be set.
+`nosync` | `false` | `true`, `false` | Whether or not to disable the initial sync. Defaults to false.
+`stripecount` | depends | [0, ∞) | Stripe count. Certain RAID configurations require this to be set.
+`stripesize` | `false` | [0, ∞) (but must be a power of 2) | The size of each stripe. If not specified, LVM will choose a sane default.
+`lvcreateoptions` | `false` | String, delimited by `;` | Extra options to be passed to LVM when creating volumes.
+
+An example is shown below
+```yaml
+apiVersion: storage.k8s.io/v1
+kind: StorageClass
+metadata:
+  name: openebs-lvm
+provisioner: local.csi.openebs.io
+parameters:
+  storage: "lvm"
+  volgroup: "lvmvg"
+  raidType: "raid1"
+  lvcreateoptions: "--vdo;--readahead auto"
+```
+
+### Test Plan
+- Provision an application on various RAID configurations, verify volume accessibility from application,
+  and verify that `lvs` reports correct RAID information.
+
+## Graduation Criteria
+
+All testcases mentioned in [Test Plan](#test-plan) section need to be automated
+
+## Drawbacks
+
+- Since the RAID options exist at the storageclass level, changes to the storage
+  class RAID options is not possible without custom logic per RAID type or manual
+  operator interactions.
+- Validation of the RAID options depend on the version of LVM2 installed as well as
+  the type of RAID used and its options. This is outside of the scope of these changes
+  and will cause users to have to debug issues with a finer comb to see why certain
+  options do not work together or on their specific machine.
+
+## Alternatives
+
+RAID can be done in either software or hardware, with many off-the-shelf products
+including built-in hardware solutions. There are also other software RAID alternatives
+that can be used below LVM, such as mdadm.
+
+This unfortunately requires operators to decouple
+the SotrageClass from the RAID configuration, but does simplify the amount of code maintained by
+this project.