Skip to content

Commit

Permalink
improve
Browse files Browse the repository at this point in the history 
Signed-off-by: Marc Schöchlin <[email protected]>
  • Loading branch information
@scoopex
scoopex committed Jun 21, 2024
1 parent 3f00ca4 commit cc017f7
Showing 1 changed file with 107 additions and 78 deletions.
185 changes: 107 additions & 78 deletions docs/guides/configuration-guide/ceph.md
View file
Original file line number Diff line number Diff line change
Expand Up @@ -201,109 +201,138 @@ is present in the file.

**Layout variants**

2. OSD only
OSISM basically utilizes LVM volumes for all OSD setup variants.

The `sda` device will be used as an OSD device without WAL and DB device.
<Tabs>

```yaml
ceph_osd_devices:
sda:
```
<TabItem value="osd_only" label="OSD only">

3. OSD + DB device
This variant does not use a dedicated wal- or db-device.
This is the most simple variant and this variant can be used if you use a all-flash setup with NVMes.

The `nvme0n1` device will be used as an DB device. It is possible to use this DB device for up to 6 OSDs. Each
OSD is provided with 30 GB.
The `sda` device will be used as an OSD device without WAL and DB volume device.

```yaml
ceph_db_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
```
```yaml
ceph_osd_devices:
sda:
```
</TabItem>

<TabItem value="osd_and_db" label="OSD + DB device">

The `nvme0n1` device will be used as an source for DB device volumes.
With the configured values the provisioning mechanism creates 6 logical volumes of 30GB size each on the nvme which can
be used for 6 OSD instances.

```yaml
ceph_db_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
```

The devices `sda` up to `sdf` will use the previously defined DB volumes from `nvme0n1` for the listed OSD instances.

```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
...
sdf:
db_pv: nvme0n1
```
</TabItem>

The `sda` device will be used as an OSD device with `nvme0n1` as DB device.
<TabItem value="osd_and_wal" label="OSD + WAL device">

```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
```
The `nvme0n1` device will be used as an source for WAL device volumes.
With the configured values the provisioning mechanism creates 6 logical volumes of 2B size each on `nvme0n1` which can
be used for 6 OSD instances.


```yaml
ceph_wal_devices:
nvme0n1:
num_osds: 6
wal_size: 2 GB
```

The devices `sda` up to `sdf` will use the previously defined WAL volumes from `nvme0n1` for the listed OSD instances.

```yaml
ceph_osd_devices:
sda:
wal_pv: nvme0n1
```
</TabItem>

4. OSD + WAL device
<TabItem value="osd_and_wal" label="OSD and DB + WAL on same device">

The `nvme0n1` device will be used as an WAL device. It is possible to use this WAL device for up to 6 OSDs. Each
OSD is provided with 2 GB.
The `nvme0n1` device will be used as an source for WAL and DB device volumes.
With the configured values the provisioning mechanism creates 6 logical DB volumes of 30GB and 6 logical WAL volumes of 2B size each
on `nvme0n1` which can be used for 6 OSD instances.

```yaml
ceph_wal_devices:
nvme0n1:
num_osds: 6
wal_size: 2 GB
```

The `sda` device will be used as an OSD device with `nvme0n1` as WAL device.
The `nvme0n1` device will be used as an DB device and a WAL device. It is possible to use those devices for up
to 6 OSDs.

```yaml
ceph_osd_devices:
sda:
wal_pv: nvme0n1
```
```yaml
ceph_db_wal_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
wal_size: 2 GB
```

5. OSD + DB device + WAL device (same device for DB + WAL)
The `sda` device will be used as an OSD device with `nvme0n1` as DB device and `nvme0n1` as WAL device.

The `nvme0n1` device will be used as an DB device and a WAL device. It is possible to use those devices for up
to 6 OSDs.
```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
wal_pv: nvme0n1
```

```yaml
ceph_db_wal_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
wal_size: 2 GB
```
In the example shown here, both the data structures for the RocksDB and for the write-ahead log are placed on the faster NVMe device.
(This is described in the [Ceph documentation](https://docs.ceph.com/en/latest/rados/configuration/bluestore-config-ref/) as "...whenever a DB device is specified but an explicit WAL device is not, the WAL will be implicitly colocated with the DB on the faster device...").

The `sda` device will be used as an OSD device with `nvme0n1` as DB device and `nvme0n1` as WAL device.
</TabItem>

```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
wal_pv: nvme0n1
```
<TabItem value="osd_and_wal" label="OSD and DB + WAL different device">

6. OSD + DB device + WAL device (different device for DB + WAL)
The `nvme0n1` device will be used as an source for WAL and `nvme1n1` for DB device volumes.
With the configured values the provisioning mechanism creates 6 logical volumes of 30 GB and 6 logical WAL volumes of 2B size each.

The `nvme0n1` device will be used as an DB device. It is possible to use this DB device for up to 6 OSDs. Each
OSD is provided with 30 GB.
```yaml
ceph_db_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
```

```yaml
ceph_db_devices:
nvme0n1:
num_osds: 6
db_size: 30 GB
```
The `nvme1n1` device will be used as an WAL device. It is possible to use this WAL device for up to 6 OSDs. Each
OSD is provided with 2 GB.

The `nvme1n1` device will be used as an WAL device. It is possible to use this WAL device for up to 6 OSDs. Each
OSD is provided with 2 GB.
```yaml
ceph_wal_devices:
nvme1n1:
num_osds: 6
wal_size: 2 GB
```

```yaml
ceph_wal_devices:
nvme1n1:
num_osds: 6
wal_size: 2 GB
```
The `sda` device will be used as an OSD device with `nvme0n1` as DB device and `nvme1n1` as WAL device.

The `sda` device will be used as an OSD device with `nvme0n1` as DB device and `nvme1n1` as WAL device.
```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
wal_pv: nvme1n1
```
</TabItem>

```yaml
ceph_osd_devices:
sda:
db_pv: nvme0n1
wal_pv: nvme1n1
```
</Tabs>

### Rollout the configured layout
### Provision the configured layout

1. Commit and push the configuration to your configuration repository
2. Establish the changed configuration
Expand Down

0 comments on commit cc017f7

Please sign in to comment.