technical - Can "backup" be used as a verb in the context of data management?

You wrote

Has to backup (or to back up) become part of the English language?

Certainly it has. You can Google your way to millions of further examples on the Web.

Your question also draws attention to the phenomenon whereby some computing-related phrasal verbs consisting of verb + preposition are being treated by many people as single merged entities, at least in the present tense. Thus to back up becomes to backup, and to log in becomes to login.

The ultimate result of this incipient process may be that the past tense of these novel verbs will also change (or at least become widely accepted), e.g. she backed up her hard drive may become she backupped her hard drive; they all logged in at the same time may become they all loginned at the same time.

At my time/space coordinates, Googling backuped already garners about 360,000 hits, and backupped about 22,000. Similarly, logined accounts for some 127,000 hits, and loginned about 40,000.

It will be interesting to see what happens.