- Sun Storage Virtual Tape Library VTL User Guide

Key VTL features and options
96267 • G Chapter 1 Introduction: VTL appliances and enterprise data-protection 9
controlsNDMP agentsoftwareon thefiler(D below).Thisagentsoftwarecopies
datafromthefilerovertheSANtovirtual tapevolumes(
E)mountedbythebackup
mediaserver(
F),sonosoftwrehastobehostedontheVTLappliance.
VTLhighavailabilityoption
InaVTLhighavailabilitysystem,intelligentselfmonitoringsoftware,redundant
hardware,andhighavailabilityLANandSANconfigurationsprotectboththedata
pathan dyourabilitytomanagestorage.Tohelpyoutobetterunderstandthesteps
inthefailoverconfigurationproc e ss,this section providesahighle veldescriptionof
thethreekeycomponentsofthehi ghavailabilityVTLsolution:
“Servernodefailoveronpage 9
“Managementpathfailoveronpag e 10
“Storagepathfailoveronpa ge 11.
Servernodefailover
TheSunStorageTekVTLhighavailabilityoptionusestwose rvernodes,each
configuredtomonitor itscompanion.Eachmemberofthepai rservesastheprimary
serverforitsown storageclientsandasthesecondary,standbyse rverforthoseofits
companion.Toprotectagainstserverfailure s,eachserversends
heartbeat
informationtoitssecondaryusingaserviceIPaddress.Ifheartbeat information
indicatesa fatalerrorinacompanionserversprocesses,thehealthyservernoti fies
itscompa n ion thatitisassumingprimaryserverresponsibilityforbothsets of
clientsandinitiatesfailover.Iftheheartbeatinformationstopsaltogether, the
healthyserverimmediatelyinitiatesfailover.Finally,ifaprimaryse rversown,self
monitoringroutinesdetectastoragedeviceconnectivityfailureandcannot
determineifthefailureislocal,theprima ryreportsthefailuretoitscompanionvia
theheartbeatsignal.Ifthe companion,secondaryservercanaccessalldevices,
physical
tape
library
VTL appliance
NAS filer
media server
Data-mover software on NAS filer copies data over SAN to virtual tapes.
SAN fabric
Ethernet LAN
virtual
tape
library
D
E
F