Taking backup remotely using innobackupex

I suspect you are confusing innobackupex with something like mysqldump. The former backs up the actual table files, while the latter connects to the database server and pulls the data.

Since it is trying to backup the database files it will of course need access to the filesystem on the database server, and can't be run remotely.

What you can do is stream the contents of the backup to a remote machine:

innobackupex --stream=tar ./ | ssh user@desthost "cat - > /data/backups/backup.tar"

Or just save the resulting backup file onto a different server with the method of your choice (e.g. shared drive, scp, rsync)