RBD Incremental Backup

“rbd diff v1\n”

Metadata records

Every record has a one byte “tag” that identifies the record type,followed by some other data.

Metadata records come in the first part of the image. Order is notimportant, as long as all the metadata records come before the datarecords.

These records come in the second part of the sequence.

“rbd diff v2\n”

Every record has a one byte “tag” that identifies the record type,followed by length of data, and then some other data.

Metadata records come in the first part of the image. Order is notimportant, as long as all the metadata records come before the datarecords.

In v2, we have the following metadata in each section:(1 Bytes) tag.(8 Bytes) length.(n Bytes) data.

In this way, we can skip the unrecognized tag.

These records come in the second part of the sequence.