DHCP Overview
14-2 DHCP Server Configuration
address,theMACaddresstowhichitisassigned,theleaseexpiration,andwhethertheaddress
assignmentisdynamic(automatic)orstatic(,manual).TheDHCPleasedatabaseisstoredinflash
memory.
InadditiontoassigningIPaddresses,theDHCPservercanalsobeconfiguredtoassignthe
followingtorequesting
clients:
•Defaultrouter(s)
•DNSserver(s)anddomainname
•NetBIOSWINSserver(s)andnodename
• Bootfile
•DHCPoptionsasdefinedbyRFC2132
Configuring a DHCP Server
OntheC2,therearetwowaystoconfigureaDHCPserver:oneistoassociatetheDHCPaddress
poolwiththeswitch’shostportIPaddress,andtheotheristoassociatetheDHCPaddresspool
witharoutedinterface.
SinceonaC2system,thehostportIPaddress
cannotfallwithinaconfiguredroutedinterfaceon
thesystem,atypicalC2systemconfiguredwithroutinginterfaceswillnothaveahostportIP
address.Therefore,allDHCPpoolswouldbeassociatedwithroutedinterfaces.
ThefollowingtasksprovidebasicDHCPserverfunctionalitywhentheDHCPpoolisassociated
with
thesystem’shostIPaddress.ThisprocedurewouldtypicallybeusedwhentheC2systemis
NOTconfiguredforrouting.
1. Configurethesystem(stack)hostportIPaddresswiththesetipaddresscommand.Oncethe
system’sIPaddressisconfigured,thesystemthen“knows”abouttheconfiguredsubnet.For
example:
set ip address 192.0.0.50 mask 255.255.255.0
2. EnableDHCPserverfunctionalityonthesystemwiththesetdhcpenablecommand.
3. ConfigureanIPaddresspoolfordynamicIPaddressassignment.Theonlyrequiredstepsare
tonamethepoolanddefinethenetworknumberandmaskforthepool.Notethatthepool
hastobeinthe
samesubnetandusethesamemaskasthesystemhostportIPaddress.For
example:
set dhcp pool auto-pool network 192.0.0.0 255.255.255.0
AllDHCPclientsservedbythisswitchmustbeinthesa meVLANas thesystem’shostport.
ThefollowingtasksprovidebasicDHCPserverfunctionalitywhentheDHCPpoolisassociated
witharoutedinterface.
1. CreateaVLANandaddportstotheVLAN.OnlyDHCPclientsassociatedwiththisVLAN
willbeservedIPaddressesfromtheDHCPaddresspoolassociatedwiththisroutedinterface
(VLAN).Inthisexample,VLAN6iscreatedandportsge.1.1throughge.1.10areaddedto
VLAN6:
set vlan create 6
set port vlan ge.1.1-10 6
Note: A total of 16 address pools, dynamic and/or static, can be configured on the SecureStack C2.