Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 6 Programmability
Configuring Programmability Components
3.
The switch sends the DHCP request for the IP address.
4. The switch receives the DHCP acknowledgment packet from the server, downloads the image
specified in the
filename variable in the DHCP server, and then boots up with downloaded
image.
While booting, the switch receives the Option 43 list from the DHCP server with information
about the location of configuration file, script file and ova file to be downloaded.
5.
After POST is complete, the switch looks for the startup configuration files, script files, and ova
files as mentioned in the Option 43 list received in Step 4. If the files mentioned the Option 43
list are present in the specified location, the switch downloads them.
The script file is downloaded to— bootflash:pxe/scripts folder
The ova file is downloaded to— bootflash:pxe/ova folder.
Figure 6-2 PXE Boot Process Flow
3
54901
ROMMON DHCP Server DNS Server*
TFTP or HTTP
Server
A u to b oot with
option 4, 5 or 6
V a lid a te d a t a
DHCP_DI S COVER
DHCP_OFFER
DHCP_REQUE S T
DHCP_ACK
Config u re m a n a gement
interf a ce with DHCP d a t a
(IP, sub net m as k, g a tew a y,
DN S s erver*
DHCP d a t a for l a ter downlo a d Re s olve re qu e s t (URL to IP)
DN S re s pon s e (IP)
HTTP or TFTP downlo a d (Im a ge) - s t a rt
HTTP or TFTP downlo a d (Im a ge) - complete
HTTP or TFTP downlo a d - s t a rt
( s t a rt u p-config, s cript s , a nd ov a file s )
HTTP or TFTP downlo a d - complete
( s t a rt u p-config, s cript s , a nd ov a file s )
Boot kernel from im a ge
Repl a ce the exi s ting s y s tem s t a rt u p-
config u r a tion file s with downlo a ded
s t a rt u p-config u r a tion file s
Contin u e b ooting Ci s co IO S
* DN S S erver s tep s do not a pply if yo u a re us ing a TFTP S erver