Supermicro L2 User manual

L2 / L3 Switches
Internet Protocol (IP)
Configuration Guide
Revision 1.0

Supermicro L2/L3 Switches Configuration Guide
2
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Supermicro L2/L3 Switches Configuration Guide
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Contents
1 IP Configuration Guide .......................................................................................................................... 4
1.1 IP Overview ................................................................................................................................... 4
1.2 Layer 3 Interface ........................................................................................................................... 5
1.2.1 Physical L3 Interface ............................................................................................................. 5
1.2.2 Layer 3 VL N Interface .......................................................................................................... 7
1.2.3 Loopback Interface ................................................................................................................ 9
1.3 Inter-VL N Routing ..................................................................................................................... 10
1.4 Static Route ................................................................................................................................. 12
1.5 RP .............................................................................................................................................. 14
1.6 DHCP ........................................................................................................................................... 16
1.6.1 DHCP Server ........................................................................................................................ 17
1.6.2 DHCP Client ......................................................................................................................... 25
1.6.3 DHCP Relay gent ............................................................................................................... 27
1.7 VRRP ............................................................................................................................................ 29

Supermicro L2/L3 Switches Configuration Guide
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1IP Configuration Guide
This document describes the system features supported in Supermicro Layer 2 / Layer 3 switch products.
This document covers the system configurations for the below listed Supermicro switch products.
The majority of this document applies to the above listed Supermicro switch products. In any particular
sub section however, the contents might vary across these product models. In those sections the
differences are clearly identified with reference to a particular model(s). If any particular model is not
referenced, the reader can safely assume that the content is applicable to all the above listed models.
Throughout this document, the common term “switch” refers to any of the above listed
Supermicro switch models unless a particular model is noted.
1.1IP Overview
Internet Protocol (IP), the foundation of the IP protocol suite, is a packet-based protocol used for the
exchange of data over computer networks. IP is a network layer that contains addressing and control
information to allow routing of data packets. IP handles addressing, fragmentation, reassembly, and
protocol de-multiplexing.
Supermicro switches support both TCP and UDP at the transport layer for maximum flexibility in
services.
•Transmission Control Protocol (TCP) is a connection-oriented protocol built upon the IP layer.
TCP specifies the format of data and acknowledgments used in the transfer of data and also the
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• SSE-G24-TG4
• SSE-G48-TG4
• SSE-X24S
• SSE-X3348S
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Blade Switches
• SBM-GEM-X2C
• SBM-GEM-X2C+
• SBM-GEM-X3S+
• SBM-XEM-X10SM

Supermicro L2/L3 Switches Configuration Guide
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procedures used to ensure that the data arrives in correct order. With TCP, multiple applications
on a system can communicate concurrently as it handles all de-multiplexing of the incoming
traffic among the application programs.
•With UDP, applications can send messages(also called datagrams) to other hosts on an IP
network without prior setup of transmission channels or data paths. UDP is suitable when error
checking and correction is either not necessary or performed in the application, avoiding the
overhead of such processing at the network interface level.
The following features of IP implementation in Supermicro switches are covered in this document.
•Layer3 Interface
•Inter-VL N routing
•Static Route
•RP
•DHCP
•VRRP
1.2Layer 3 Interface
The network layer, or Layer 3,handles the routing of data in packets acrosslogical internetwork paths.
The data link layer, or Layer 2,contains protocols that control the physical layer (Layer 1) and data
framing for transmission on the physical medium. The Layer 2 function of filtering and forwarding data
in frames between two segments on a L N is known as bridging.
Supermicro switches support three types of Layer 3 interfaces.
•The Layer 3VLAN Interface combines the functionality of routing and bridging.
•The physical Layer 3 interface allows the switch to be configured like a traditional router. It is
also referred as a Routed Interface.
•The Loopback Interface is a logical interface that is “always up”. It is not tied to any physical
interface therefore it does not go down unless it is administratively shut down.
The Layer3 interface is used to:
•llow traffic to be routed between VL Ns.
•Provide Layer 3 IP connectivity to the switch.
1.2.1 Physical L3 Interface
The physical Layer 3 interfaces support functionalities similar to a traditional router. Routed ports are
physical ports on the switch that act like a router interface with an IP address configured; they do not
belong to any VL N.
Supermicro switches support Secondary IP addresses, hich are used when the same physical segment
of the switch interface that is connected serves multiple logical networks.

Supermicro L2/L3 Switches Configuration Guide
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Follow the steps below to configure a Physical Layer3 Interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode
Step 2
interface
<
interface
-
type
><
interface
-
id
>
or
interface range <interface-type><interface-id> ….
Enters
the interface configuration
mode.
1.2.2
interface-type – may be any of the
following:
gigabitethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
1.2.3
interface-id is in slot/port format for all
physical interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hyphen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
1.2.4
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
1.2.5
If multiple interfaces are provided, the
next step will perform the particular
configuration on all these interfaces.
Step 3
no s itchport
Configure
s the
router port
Step 4
ip address [<ip
-
address> | <ip
-
address>/prefix
-
length] [<subnet-mask>] [secondary]
Configure
s the
IP address.
ip-address – valid IPv4 address.
ip-address/prefix-length - valid IPv4

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a
ddress with a prefix length of value 1
-
32.
subnet-mask – valid IP subnet mask.
1.2.6
Secondary - ssigns multiple IP
addresses to network interfaces.
Step 5
end
Exi
ts the configuration mode.
Step 6
s
ho
ip interface
1.2.7
Displays the
Layer 3
interface
information.
IP Routing is enabled by default in Supermicro switches.
The “s itchport” command deletes the Physical Layer 3 interface and the interface is reset
as a Layer2 interface.
The example below shows the commands used to configure a Physical Layer3 Interface.
SMIS# configure terminal
SMIS(config)# interface Gi 0/22
SMIS(config-if)# no s itchport
SMIS(config-if)# ip address 20.20.20.1 255.255.255.0
SMIS(config-if)# end
SMIS# sho ip interface
Gi0/22 is up, line protocol is up
Internet address is 20.20.20.1/24
Broadcast address is20.20.20.255
mgmt is up, line protocol is down
Internet address is 192.168.100.102/24
Broadcast address is192.168.100.255
Gateway 0.0.0.0
1.2.8 Layer 3 VL N Interface
VL Ns typically operate at Layer 2. When aLayer2 VL N is configured with an IP address, it behaves as a
logical Layer 3 VL N interface. L3 VL N interface provides logical routing interfaces to VL Ns on Layer

Supermicro L2/L3 Switches Configuration Guide
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2 switches.It is also called aS itch Virtual Interface (SVI )and handles processing for all the packets
associated with that VL N.
Follow the steps below to configure a Logical Layer3 Interface.
Step Command Description
Step 1
configure terminal
Enters the co
nfiguration mode
Step 2
Create a Layer 2 VLAN and add all required ports.
For details on configuring
a
Layer 2
VL N, refer to the ‘VL N Config. guide’
at www.supermicro.com
Step 3
interface
vlan<vlan
-
id (1
-
4069)>
E
nter
s
the
interface configuration mode
to specify the interface to be
configured as a Layer 3 interface.
Step 4
ip address [<ip
-
address> | <ip
-
address>/prefix
-
length] [<subnet-mask>] [secondary]
Configure
s
the
IP address.
ip-address – valid IPv4 address.
ip-address/prefix-length - valid IPv4
address with a prefix length of value 1-
32.
subnet-mask – valid IP subnet mask.
Secondary - ssigns multiple IP
addresses to network interfaces.
Step
5
end
Exits the configuration mode.
Step
6
s
h
o
ip interface
Displays the Layer 3 interface
information.
The “
no ip address [<ip_addr>]
”
command
deletes the
L
ayer 3 VL N interface and
resets
it
as a Layer2 VL N.
The example below shows the commands used to configure a Logical Layer3 interface.
SMIS# configure terminal
SMIS(config)# vlan 10
SMIS(config-vlan)# ports Gi 0/22 untagged
SMIS(config-vlan)# exit
SMIS(config)# interface vlan 10
SMIS(config-if)#ip address 10.10.10.1 255.255.255.0
SMIS(config-if)# end

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SMIS# sho ip interface
mgmt is up, line protocol is down
Internet address is 192.168.100.102/24
Broadcast address is 192.168.100.255
Gateway 0.0.0.0
vlan10 is up, line protocol is up
Internet address is 10.10.10.1/24
Broadcast address is 10.10.10.255
1.2.9 Loopback Interface
Supermicro switches support a loopback interface, which is a virtual interface and is not connected to
any other device. Loopback interfaces are very useful since they will never go down unless the entire
router goes down. This is useful for managing routers because there will always be at least one active
interface on the routers: the loopback interface.
Follow the steps below to configure loopback interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode
Step
2
interface
lo
opback <interface
-
id (1
-
100)>
E
nter
s
interface configuration mode
to
specify the interface to be configured
as a Layer 3 interface.
Step
3
ip address [<ip
-
address> | <ip
-
address>/prefix
-
length] [<subnet-mask>]
Configure IP address.
ip-address – valid IPv4 address.
ip-address/prefix-length - valid IPv4
address with a prefix length of value 1-
32.
subnet-mask – valid IP subnet mask.
NOTE: Subnet mask should be 32-bit for
loopback interface.
Step 4
no shutdo n
Enable the
l
oopback interface
S
tep
5
end
Exits the configuration mode.
Step
6
sho ip interface
sho interface loopback <1-100>
Displays the
Layer 3 interface
configuration.
Display the loopback interface

Supermicro L2/L3 Switches Configuration Guide
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configuration.
IP Routing is not supported on
l
oopback
i
nterfaces.
The “nointerface loopback <interface-id (1-100)>” command deletes the loopback
interface.
SMIS# configure terminal
SMIS(config)# interface loopback 1
SMIS(config-if)# ip address 100.1.1.1/32
SMIS(config-if)# no shutdo n
SMIS(config-if)# end
SMIS# sho interface loopback 1
Interface Status Protocol Description
--------- ------ -------- -----------
loopback1upup
SMIS# sho ip interface
mgmt is up, line protocol is down
Internet address is 192.168.100.102/24
Broadcast address is 192.168.100.255
Gateway 0.0.0.0
loopback1 is up, line protocol is up
Internet address is 100.1.1.1/32
Broadcast address is 100.1.1.1
1.3Inter-VL N Routing
VL Ns enable splitting traffic across several manageable broadcast domains. Devices within a VL N can
communicate with one another without requiring routing. Whenever hosts in one VL N need to
communicate with hosts in another VL N, the traffic must be routed between them. This is known as
Inter-VLAN Routing.
Supermicro switches use application-specific integrated circuits ( SICs), which are hardware chips that
can route traffic at very high speeds. These SICs are installed on the switching engine of a Layer 3
switch, which traditionally switches frames at Layer 2. The SICs allow the switching engine to also
switch frames that contain packets sent between different VL Ns. Each SIC is programmed with the
information required to route traffic from one VL N to another, ithout having to pass the traffic
through the CPU of the routing engine.
dvantages of Inter-VLAN routing in L3 s itches:

Supermicro L2/L3 Switches Configuration Guide
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•Layer 3 switches are much more cost effective than routers for delivering high-speed inter-VL N
routing.
•Layer 3 switches are enhanced Layer 2 switches, and therefore have the same high port
densities as Layer 2 switches. Routers on the other hand typically have a much lower port
density.
•Layer 3 switches can be configured to operate as a normal Layer 2 switch or Layer 3 switch as
required.
Application of Inter-VLAN routing:
The network can be divided based on the group or function of itsdevices. For example, an engineering
department VL N would only have devices associated with the engineering department, while an HR
VL N would only have HR related devices. With Inter-VL N routing, the devices in each VL N can talk to
one another without all the devices being in the same broadcast domain.
Figure IP-1: Inter-VLAN Routing
Follow the steps below to configure Inter-VL N routing.
1. Create two Layer 3 interface VL Ns.
2. Configure an IP address for both interfaces of these Layer 3 VL Ns.
3. Execute show ip route to check if the VL N routes specified by VL N IP address are displayed as
connected routes. The routing table has an entry for each VL N interface subnet, therefore,
devices in VL N 10 can communicate with devices in VL N 20 and vice versa.
The example below shows the commands used to configure Inter-VL N routing.
SMIS# configure terminal
Layer3
S
witch
VLAN 200
VLAN 300
VLAN 100
To W N via Router

Supermicro L2/L3 Switches Configuration Guide
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SMIS(config)# vlan 10
SMIS(config-vlan)# ports Gi 0/21 untagged
SMIS(config-vlan)# exit
SMIS(config)# interface vlan 10
SMIS(config-if)#ip address 10.10.10.1 255.255.255.0
SMIS(config-if)# exit
SMIS(config)# vlan 20
SMIS(config-vlan)# ports Gi 0/22 untagged
SMIS(config-vlan)# exit
SMIS(config)# interface vlan 20
SMIS(config-if)# ip address 20.20.20.1255.255.255.0
SMIS(config-if)# end
SMIS# sho ip interface
mgmt is up, line protocol is down
Internet address is 192.168.100.102/24
Broadcast address is 192.168.100.255
Gateway 0.0.0.0
vlan10 is up, line protocol is up
Internet address is 10.10.10.1/24
Broadcast address is 10.10.10.255
vlan20 is up, line protocol is up
Internet address is 20.20.20.1/8
Broadcast address is 20.255.255.255
SMIS# sho ip route
C 10.10.10.0/24 is directly connected, vlan10
C 20.0.0.0/8 is directly connected, vlan20
C 192.168.100.0/24 is directly connected, mgmt
1.4Static Route
static route defines an explicit path between two routers. Manual reconfiguration of static routes is
required whenever network changes occur. Static routes use less bandwidth than dynamic routes. No
CPU cycles are used to calculate and analyze routing updates.
Routers forward packets using either route information from manually configured route table entries or
by using the route information calculated with dynamic routing algorithms.
Use of Static Routes:

Supermicro L2/L3 Switches Configuration Guide
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•Static routes can be used in environments where network traffic is predictable and the network
design is simple.
•Static routes are also useful for specifying a gateway of last resort (a default router to which all
non-routable packets are sent).
Follow the steps below to configure a static route.
Step Command Description
Step 1
configure terminal
Enters the configuration mode
Step 2
ip route <prefix><mask> {<next
-
hop> | Vlan<vlan
-
id (1-4069)> | <interface-type><interface-id> |
null0 } [<distance (1-255)>] [ private ]
Configure
s the
static route. The VL N id
and interface for this static route.
Prefix –The destination network IP
address the route leads to.
Mask – valid IP subnet mask
1.4.1
Next-hop – specifies the next-hop IP
address.
Null - Specifies a null interface
1.4.2
Distance – Specifies the administrative
distance in the range of 1 to 255. The
default is 1.
Private- Specifies whether this route
can be shared with other routes when
RIP is enabled.
Step 3
end
Exits the configuration mode.
Step 4
sho ip route [ { <ip
-
address> [<mask>] | bgp |
connected | ospf | rip | static | summary } ]
Displays the
route information
W
hen an interface goes down, static routes through that interface are removed
from the IP
routing table.
When the next hop for the address is unreachable, the static route is removed from the IP
routing table.
The “no ip route <prefix><mask> { <next-hop> | Vlan<vlan-id(1-4069)> | <interface
-type><interface-id> | null0 } [private]” command deletes the static route.

Supermicro L2/L3 Switches Configuration Guide
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The example below shows the commands used to configure a static route.
SMIS# configure terminal
SMIS(config)# vlan 10
SMIS(config-vlan)# ports Gi 0/21 untagged
SMIS(config-vlan)# exit
SMIS(config)# interface vlan 10
SMIS(config-if)# ip address 10.10.10.1
SMIS(config-if)# exit
SMIS(config)# ip route 200.200.200.0 255.255.255.0 10.10.10.2
SMIS(config)# end
SMIS# sho ip route static
S 200.200.200.0/24 [1] via 10.10.10.2
1.5 RP
The ddress Resolution Protocol ( RP) feature finds the hardware address, also known as the Media
ccess Control (M C) address, of a host from its known IP address. This mapping of M C addresses to IP
addresses is stored in a table called the ARP cache.
RP is part of all Supermicro switches systems that run IP. Though Supermicro switches are Layer 3
switches that forward packets based on IP address, RP is required for certain cases like default
gateways or for pinging within the same subnet.
1.5.1.1 Cache Timeout
The RP cache can contain both dynamic (learned) entries and static (user-configured) entries. Dynamic
RP entries are created in the RP cache when the Layer 3 switch learns a device’s M C address from
an RP request or from the RP reply from a device. RP entries are refreshed periodically, otherwise
they will time out and be deleted from the RP cache.
1.5.1.2 ARP Request Retry
RP requests can be resent by a device before confirming the host as unreachable. The number of times
RP requests can be retransmitted is user configurable in Supermicro switches.
1.5.1.3 Static ARP
For hosts that do not support dynamic ddress Resolution Protocol( RP), static entries can be added by
defining the static mapping between an IP address (a 32-bit address) and a Media ccess Control (M C)
address (a 48-bit address). Static RP entries in the RP cache never time out. The entries remain in the
RP table until they are removed by the user configuration.

Supermicro L2/L3 Switches Configuration Guide
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Defaults
Parameter Default Value
RP request retr
ies
3
RP cache timeout
300
Static RP entrie
s
None
Follow the steps below to configure the RP.
Step Command Description
Step 1
configure terminal
Enters the configuration mode
Step 2
arp timeout <seconds (30
-
86400)>
(Optional)
Sets the length of time, in
seconds, an ddress Resolution
Protocol ( RP) cache entry stays in the
cache. The range is 30-86400 seconds.
Note: If there are frequent changes to
cache entries in a network ,a shorter
RP timeout is recommended.
Step 3
arp<ip address><hard are address> {Vlan<vlan
-
id(1-4069)> | <interface-type><interface-id> |
Linuxvlan<interface-name>| Cpu0}
(Optional)
Globally associates an IP
address with a M C address in the RP
cache.
ip-address—IP address in four-part
dotted decimal format corresponding
to the local data-link address.
hard are-address—Local data-link
address (a 48-bit address).
Linuxvlan - Interface name of a Linux
VL N interface.
Cpu0 - Out-of-band management
interface
Step
4
iparp max
-
retries <value (2
-
10)>
(Optional)
S
et
s
the maximum number
of RP request retries in the range of 2-
10.
Step
5
end
Exits the configuration mode.
Step
6
sho iparp
sho iparp summary
sho iparp information
Displays the
RP table
entries.
Displays a summary of the RP table,
including dynamic and static entries.
Displays the RP configuration details.

Supermicro L2/L3 Switches Configuration Guide
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These commands delete values or reset to default values, as applicable:
no arp timeout
no arp<ip address>
no iparp max-retries
The example below shows the commands used to configure the RP.
SMIS# configure terminal
SMIS(config)# arp timeout 800
SMIS(config)# iparp max-retries 10
SMIS(config)# arp 10.0.0.0 48:2C:6A:1E:59:3D vlan 1
SMIS(config)# end
SMIS# sho iparp
ddress Hardware ddress Type Interface Mapping
------- ---------------- ---- --------- -------
10.0.0.0 48:2c:6a:1e:59:3d RP vlan1 Static
SMIS# sho iparp summary
1 IP RP entries, with 0 of them incomplete
SMIS# sho iparp information
RP Configurations:
-------------------
Maximum number of RP request retries is 10
RP cache timeout is 800 seconds
1.6DHCP
The Dynamic Host Configuration Protocol (DHCP) is based on the Bootstrap Protocol (BOOTP), which can
automatically allocate reusable network addresses and configuration options to Internet hosts. DHCP is
built on a client/server model where designated DHCP servers allocate network addresses and deliver
configuration parameters to DHCP clients.
When a DHCP client requests an IP address from a DHCP server, the client sends a DHCPDISCOVER
broadcast message to locate a DHCP server. relay agent forwards the packets between the DHCP
client and the server. DHCP server offers configuration parameters (such as an IP address, M C
address, domain name, and a lease for the IP address) to the client in a DHCPOFFER unicast message.

Supermicro L2/L3 Switches Configuration Guide
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Supermicro switches support Dynamic Host Configuration Protocol (DHCP) server, DHCP client and DHCP
relay agent functionality.
1.6.1 DHCP Server
The DHCP server implementation in Supermicro switches maintains a database of available IP addresses
and configuration information. When the DHCP server receives a request from a DHCP client, the DHCP
server determines the network to which the DHCP client is connected. The DHCP server then allocates
an IP address or prefix that is appropriate for the client. DHCP servers typically grant IP addresses to
clients only for a limited interval. DHCP clients must either renew their IP address before that interval
has expired or must stop using the address once the interval has expired. The DHCP server can also be
configured to assign additional parameters like default routers, the IP address of the Domain Name
System (DNS) server,etc. The DHCP server can accept broadcasts from locally attached L N segments or
from DHCP requests that have been forwarded by other DHCP relay agents within the network.
Figure IP-2: DHCP Server
1.6.1.1 DHCP Address Pool
The DHCP server in Supermicro switches accepts requests for address assignment and renewals. It
assigns the addresses from predefined groups of addresses contained within DHCP address pools. These
address pools can also be configured to supply additional information to the requesting client such as
the IP address of the DNS server, the default router, and other configuration parameters.
1.6.1.2 Additional Parameter Default Router & DNS
The DHCP server can be configured to assign additional parameters to the DHCP clients such as the IP
address of the Domain Name System (DNS) server and the default router.
DHCP
Server
DHCP
Client
DHCP Discover
DHCP Ack
DHCP Offer
DHCP Request

Supermicro L2/L3 Switches Configuration Guide
18
The default route IP address should be on the same subnet as the client. When a DHCP client requests
an IP address, the DHCP server accesses the default router list to select another router that the DHCP
client is to use as the first hop for forwarding messages.
1.6.1.3 Excluding IP Addresses
By default, the DHCP Server assumes all IP addresses in the configured DHCP address pool are available
for assigning to DHCP clients. If a particular address or range of addresses should not be assigned to
DHCP clients, users can configure these as excluded IP addresses.
1.6.1.4 Utilization Threshold
DHCP address pool has a threshold associated with it. If a pool’s outstanding addresses exceed the
high utilization threshold and SNMP trap signaling is enabled, SNMP is notified.
1.6.1.5 Lease
DHCP supports three mechanisms for IP address allocation:
• utomatic allocation: the DHCP server assigns a permanent IP address to a client.
• Dynamic allocation: the DHCP server assigns an IP address to a client from the address pool for either a
limited period of time called a lease or until the client relinquishes the address.
• Manual allocation: the network administrator assigns an IP address to a client and DHCP is used simply
to convey the assigned address to the client.
1.6.1.6 Options and Sub options
Configuration parameters and control information are available inthe options field of the DHCP
message. This can be used when additional information need not be stored in DHCP client, rather it can
be transmitted by the DHCP server to the client.
Some DHCP clients send a client identifier (DHCP option 61) in the DHCP packet to the DHCP server.
Configuring manual bindings for such clients is done in the client-identifier DHCP pool configuration. To
configure manual bindings for clients who do not send a client identifier option, configure the hardware-
address DHCP pool configuration.
1.6.1.7 Boot File
The boot file is used to store the boot image for the client. The boot image is generally the operating
system the Dynamic Host Configuration Protocol (DHCP)client uses to load.
1.6.1.8 DHCP Ping
The DHCP server pings a pool address twice before assigning a particular address to a requesting client.
If the ping is unanswered, the DHCP server assumes that the address is not in use and assigns the
address to the requesting client.
1.6.1.9 DHCP Server Configuration
Defaults
Parameter Default Value
DHCP server
status
Disabled
DHCP
s
erver IP address
None

Supermicro L2/L3 Switches Configuration Guide
19
DHCP pool index
None
DHCP network IP
None
Excluded
a
ddress
None
Domain
n
ame
None
DNS server
None
NetBIOS name server
None
NetBIOS node type
None
DHCP option
None
Lease
3600
Utilization
t
hreshold
75
Default router
None
Hardware
a
ddress
None
Client ID
None
Bootfile
None
Next
-
server
None
DHC
P ping
None
Offer reuse
5
1.6.1.9.1 Enabling a DHCP Server
The DHCP server is disabled by default in Supermicro switches. Follow the steps below to enable a DHCP
server.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
service dhcp
-
server
Enable
the
DHCP server.
Step 3
end
Exits the configuration mode.
Step 4
sho ipdhcp server information
Displays the DHCP server configuration
details.
The
DHCP
r
elay must be disabled before enabling
the
DHCP
s
erver.
The ‘noservice dhcp-server’ command disables the DHCP server.
1.6.1.9.2 Configuring the DHCPPool
Follow the steps below to configure the DHCP server pool.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
ipdhcp pool <index (1
-
214
7483647)>
Creates a name for the DHCP server

Supermicro L2/L3 Switches Configuration Guide
20
address pool and enters
the
DHCP poo
l
configuration mode.
Step 3
net ork <net ork
-
IP> [ { <mask> | / <prefix
-
length (1-31)> } ] [<start-ip> [<end-ip>]]
Specifies the subnet network number
and mask of the DHCP address pool.
Net ork-ip – valid IPv4 address.
prefix-length - valid IPv4 address with
a prefix length value of 1-32.
mask – valid IP subnet mask.
start-ip and end-ip specifies the address
pool range
Step 4
excluded
-
address <lo
-
address><
hig
h
-
address >
(Optional)
Specif
ies
the range of
IP
addresses that the DHCP server must
not assign to DHCP clients in the range
of lo -address to high-address.
Step 5
domain
-
name <domain (63)>
(Optional)
Specifies the domain name
for the client.
Step 6
dns
-
server <ip address>
(Optional) Specifies the IP address of a
DNS server that is available to a DHCP
client.
Step 7
netbios
-
name
-
server <ip address>
(Optional) Specifies the NetBIOS WINS
server that is available to a Microsoft
DHCP client.
Step 8
netbios
-
node
-
type { <0
-
FF> | b
-
node | h
-
node |
m-node | p-node }
(Optional) Specifies the NetBIOS node
type for a Microsoft DHCP client.
1.6.2
b-node – Broadcast node
h-node – Hybrid node
m-node – Mixed node
p-node – Peer to peer node
Step 9
option <code (1
-
2147483647
)> { ascii<string> |
hex <Hex String> | ip<address> }
(Optional) Configures
the
DHCP server
options.
1.6.3
Configurable DHCP options with their