Information Technology Reference
In-Depth Information
Backup and Restore/Recovery:. While.backup.is.a.routine.
that.is.well.understood,.the.ability.to.restore.data.is.usu-
ally.only.performed.when.data.are.lost,.corrupted,.or.
otherwise.changed..It.is.extremely.important.to.review.
and.test.the.restore.procedures,.to.ensure.that,.in.an.
emergency,. appropriate. action. can. be. taken.. A. real.
danger,.when.restoring.iles.from.the.backup,.is.that.of.
restoring. additional. iles. which. then. overwrite. newer.
iles..Were.this.to.happen.to.an.order.processing.sys-
tem. or. other. system. that. records. transactions,. such.
an.error.could.result.in.severe.loss..To.avoid.even.the.
possibility.of.such.an.error,.you.should.always.restore.
iles.to.a.speciic.location.that.is.separate.from.the.live.
iles..Then,.having.veriied.the.integrity.of.the.restored.
ile(s),.they.may.be.copied.to.the.required.area,.again,.
cautiously.and.with.consideration.for.the.risks.involved.
Backup Files:. Those.iles.that.are.retained,.often.on.high-
capacity. tape. or. a. separate. disk. subsystem,. that.
represent. the. organization's. protection. against. loss,.
damage,. or. nonavailability. of. the. data. held. on. infor-
mation.systems.. It.is.important.to.have.available.the.
most.recent.few.backups.to.enable.restore.in.case.of.
need,.and.it.is.crucial.that.recent.backup.tapes/disks.
be.stored.safely.off-site,.suficiently.far.away.to.reduce.
the.risk.of.environmental.damage.(e.g.,.lood).destroy-
ing.both.the.primary.systems.and.the.off-site.backups.
Backup Power Generators:. Usually. gasoline-driven. units.
linked. to. an
. uninterruptible. power. supply
. (UPS). to.
prevent. your. systems. crashing. as. a. result. of. power.
failure..Power.generators.should.be.of.adequate.capac-
ity.to.support.the.systems.that.require.power..Backup.
power.generators.are.rarely.used..As.a.result,.they.can.
remain.idle.for.years,.as.usually. the.UPS.will.bridge.
the.gap.until.the.power.is.either.restored,.or.the.sys-
tems. have. been. safely. shut. down.. As. a. result,. when.
needed,. the. power. generator. may. not. have. been.
tested. for. a. considerable. period.. It. is. important. that.
