1. A method comprising: receiving indexing information, wherein the indexing information is received at a deduplication server, the indexing information is collected by one or more deduplication clients during a backup operation, the indexing information represents a plurality of documents, which are divided into a plurality of data segments, and a plurality of keywords, and each of the plurality of data segments is of a predetermined size, and one or more keywords of the plurality of keywords are split between multiple data segments of the plurality of data segments; constructing an inverted index as part of the backup operation, wherein the constructing is performed by the deduplication server after deduplication of the plurality of documents and the plurality of data segments, the inverted index comprises the plurality of keywords, each keyword of the plurality of keywords maps to at least one fingerprint of a plurality of fingerprints, and each fingerprint of the plurality of fingerprints represents at least a portion of a data segment of a document of the plurality of documents; and performing a keyword search using the inverted index, wherein the keyword search identifies at least one keyword, and the performing the keyword search comprises obtaining a list of fingerprints that are mapped to the at least one keyword in the inverted index.
1. A method comprising: receiving indexing information, wherein the indexing information is received at a deduplication server, the indexing information is collected by one or more deduplication clients during a backup operation, the indexing information represents a plurality of documents, which are divided into a plurality of data segments, and a plurality of keywords, and each of the plurality of data segments is of a predetermined size, and one or more keywords of the plurality of keywords are split between multiple data segments of the plurality of data segments; constructing an inverted index as part of the backup operation, wherein the constructing is performed by the deduplication server after deduplication of the plurality of documents and the plurality of data segments, the inverted index comprises the plurality of keywords, each keyword of the plurality of keywords maps to at least one fingerprint of a plurality of fingerprints, and each fingerprint of the plurality of fingerprints represents at least a portion of a data segment of a document of the plurality of documents; and performing a keyword search using the inverted index, wherein the keyword search identifies at least one keyword, and the performing the keyword search comprises obtaining a list of fingerprints that are mapped to the at least one keyword in the inverted index. 9. The method of claim 1 , further comprising: maintaining the inverted index, wherein the maintaining comprises at least one of: updating the inverted index, or removing a duplicate copy of a fingerprint that has already been stored in the inverted index before.