Cisco WS-C2980G-A Software Guide - Page 54

Renewing and Releasing a DHCP-Assigned IP Address

Page 54 highlights

Renewing and Releasing a DHCP-Assigned IP Address Chapter 3 Configuring the Switch IP Address and Default Gateway Step 3 Step 4 Step 5 Step 6 Step 7 Task Command Add an entry for each switch in the DHCP, BOOTP, or RARP - server configuration, mapping the MAC address of the switch to the IP configuration information for the switch. (With DHCP, this step is necessary only with the manual or automatic allocation methods.) Set the sc0 interface IP address to 0.0.0.0. set interface sc0 0.0.0.0 Reset the switch. The switch broadcasts DHCP and RARP requests only when the switch boots up. reset system When the switch reboots, confirm that the sc0 interface IP show interface address, subnet mask, and broadcast address are set correctly. For DHCP, confirm that other options (such as the default gateway address) are set correctly. show ip route This example shows the switch broadcasting a DHCP request, receiving a DHCP offer, and configuring the IP address and other IP parameters according to the contents of the DHCP offer: Console> (enable) Sending RARP request with address 00:90:0c:5a:8f:ff Sending DHCP packet with address: 00:90:0c:5a:8f:ff dhcpoffer Sending DHCP packet with address: 00:90:0c:5a:8f:ff Timezone set to '', offset from UTC is 7 hours 58 minutes Timezone set to '', offset from UTC is 7 hours 58 minutes 172.16.30.32 added to DNS server table as primary server. 172.16.31.32 added to DNS server table as backup server. 172.16.32.32 added to DNS server table as backup server. NTP server 172.16.25.253 added NTP server 172.16.25.252 added %MGMT-5-DHCP_S:Assigned IP address 172.20.25.244 from DHCP Server 172.20.25.254 Console> (enable) show interface sl0: flags=51 slip 0.0.0.0 dest 0.0.0.0 sc0: flags=63 vlan 1 inet 172.20.25.244 netmask 255.255.255.0 broadcast 172.20.25.255 dhcp server: 172.20.25.254 Console> Renewing and Releasing a DHCP-Assigned IP Address If you are using DHCP for IP address assignment, you can perform either of these tasks: • Renew-Renew the lease on a DHCP-assigned IP address. • Release-Release the lease on a DHCP-assigned IP address. To renew or release a DHCP-assigned IP address on the in-band (sc0) management interface, perform one of these tasks in privileged mode: Task Renew the lease on a DHCP-assigned IP address. Release the lease on a DHCP-assigned IP address. Command set interface sc0 dhcp renew set interface sc0 dhcp release 3-10 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01

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3-10
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide
Release 8.1
78-15486-01
Chapter 3
Configuring the Switch IP Address and Default Gateway
Renewing and Releasing a DHCP-Assigned IP Address
This example shows the switch broadcasting a DHCP request, receiving a DHCP offer, and configuring
the IP address and other IP parameters according to the contents of the DHCP offer:
Console> (enable) Sending RARP request with address 00:90:0c:5a:8f:ff
Sending DHCP packet with address: 00:90:0c:5a:8f:ff
dhcpoffer
Sending DHCP packet with address: 00:90:0c:5a:8f:ff
Timezone set to '', offset from UTC is 7 hours 58 minutes
Timezone set to '', offset from UTC is 7 hours 58 minutes
172.16.30.32 added to DNS server table as primary server.
172.16.31.32 added to DNS server table as backup server.
172.16.32.32 added to DNS server table as backup server.
NTP server 172.16.25.253 added
NTP server 172.16.25.252 added
%MGMT-5-DHCP_S:Assigned IP address 172.20.25.244 from DHCP Server 172.20.25.254
Console> (enable)
show interface
sl0: flags=51<UP,POINTOPOINT,RUNNING>
slip 0.0.0.0 dest 0.0.0.0
sc0: flags=63<UP,BROADCAST,RUNNING>
vlan 1 inet 172.20.25.244 netmask 255.255.255.0 broadcast 172.20.25.255
dhcp server: 172.20.25.254
Console>
Renewing and Releasing a DHCP-Assigned IP Address
If you are using DHCP for IP address assignment, you can perform either of these tasks:
Renew—Renew the lease on a DHCP-assigned IP address.
Release—Release the lease on a DHCP-assigned IP address.
To renew or release a DHCP-assigned IP address on the in-band (sc0) management interface, perform
one of these tasks in privileged mode:
Step 3
Add an entry for each switch in the DHCP, BOOTP, or RARP
server configuration, mapping the MAC address of the switch to
the IP configuration information for the switch. (With DHCP,
this step is necessary only with the manual or automatic
allocation methods.)
Step 4
Set the sc0 interface IP address to 0.0.0.0.
set interface sc0 0.0.0.0
Step 5
Reset the switch. The switch broadcasts DHCP and RARP
requests only when the switch boots up.
reset system
Step 6
When the switch reboots, confirm that the sc0 interface IP
address, subnet mask, and broadcast address are set correctly.
show interface
Step 7
For DHCP, confirm that other options (such as the default
gateway address) are set correctly.
show ip route
Task
Command
Task
Command
Renew the lease on a DHCP-assigned IP address.
set interface sc0 dhcp renew
Release the lease on a DHCP-assigned IP address.
set interface sc0 dhcp release