The snapshots are part of the indexes, representing a point in time list of the segments in the index. When you perform the backup, the metadata (information about the cluster) and the snapshot specified indicate s which set of index files to be backup up/copied to the destination hdfs directory (as specified in the <backup> section of the source solr.xml) This blog walks through the process https://blog.cloudera.com/blog/2017/05/how-to-backup-and-disaster-recovery-for-apache-solr-part-i/ When you run the --prepare-snapshot-export, it creates a copy of the metadata, and a copylisting of all the files that will be copied by the distcp command, to the remote cluster. Then, when you execute the snapshot export, the distcp command will copy those files to the remote cluster. The -b on the restore command is just the name of the directory (represented by the snapshot name) that was created and copied by distcp. -pd ... View more