Linux.com: Using a Linux Failover Router

“Today, it’s hard to imagine an organization operating without
taking advantage of the vast resources and opportunities that the
Internet provides. The Internet’s role has become so significant
that no organization can afford to have its Net connection going
down for too long. Consequently, most organizations have some form
of a secondary or backup connection ready (such as a leased line)
in case their primary Net connection fails. However, the process of
switching over from the primary to the backup connection, if done
manually by the system administrator, can take some time, depending
upon how ready the backup setup is and on the availability of the
administrator at the right moment. The process can even become a
costly affair if the organization must buy dedicated routers for
the purpose of automatic switchover. But there is an easy and
cost-effective alternative–setting up a Linux failover
router…”

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