lbcli list changed-blocks
Returns a list of all Logical Block Addresses (LBAs) that have changed between two snapshots of a volume. You must specify either two snapshots to compare or provide a single snapshot (in which case this snapshot is compared against volume at creation time).
The result will return a list of ranges, with each range containing the range of addresses it covers and a bitmap indicating changed LBAs between the two snapshots.
The response size is limited to 10000 ranges. For large volumes/snapshots it may be required to invoke the command multiple times consecutively, each time setting the startOffset to the value of nextLBAOffset returned by the previous command.
Notes:
- Both snapshots must belong to the same volume, and the current snapshot must be newer than the base snapshot.
- Lbcli list changed blocks may optionally return a long response. Output formats -o json or -o yaml must be specified (-o ‘human-readable-format’ is not supported for this command).
- If this command fails on context timeout, contact Lightbits Support, as some minor tweaks could be required to enable inter-service communications.
lbcli list changed-blocks [flags]Examples:
lbcli -J $JWT list changed-blocks --project-name=default --current-snapshot-uuid=4c027341-7283-4b45-84f5-1460f4c96127 --base-snapshot-uuid=4c027341-7283-4b45-84f5-1460f4c96127 -o jsonlbcli -J $JWT list changed-blocks --project-name=default --current-snapshot-uuid=4c027341-7283-4b45-84f5-1460f4c96127 -o yamllbcli -J $JWT list changed-blocks --project-name=default --current-snapshot-name=snap1 --base-snapshot-name=snap2 -o jsonlbcli -J $JWT list changed-blocks --project-name=default --current-snapshot-name=snap1 -o json| Flag | Short | Type | Default | Description |
|---|---|---|---|---|
| --project-name | string | Project name (mandatory). | ||
| --current-snapshot-name/--current-snapshot-uuid | string | Snapshot name/Snapshot UUID of the newer snapshot we want to compare. Note that you should identify the snapshot by either name or UUID, never both. Only one should be used. | ||
| --base-snapshot-name/--base-snapshot-uuid | string | Snapshot name/Snapshot UUID of the older snapshot we want to compare (optional; if not provided, we will compare against the volume at the time of creation). Note that you should identify the snapshot by either name or UUID, never both. Only one should be used. | ||
| --offset-lba | uint64 | The first offset from which the comparison should start (optional). | ||
| --help | -h | bool | Help for changed-blocks. |
This command returns the following fields for each changed-block. The default output format is human-readable.
| Field | Type | Description |
|---|---|---|
| lbaRanges | LBARange | Up to 10,000 LBA (Logical Block Address) ranges. |
| nextOffsetLBA | uint64 | The end offset in the current response/offset, from which to start a new request. |
LBARange
| Field | Type | Description |
|---|---|---|
| lbaStart | uint64 | The first LBA in this range. |
| lbaEnd | uint64 | The last LBA in this range. |
| dataBitMap | bytes/string | A bits set indicating which LBAs have changed. The order of bits runs from left to right, with the MSB bit indicating the lowest address. |