System information

Troubleshooting Hardware and Booting Problems 3-47
Booting: Router Cannot Netboot from TFTP Server
Possible Problem Solution
Network is
disconnected
or isolated
Step 1 Boot the router from ROM or Flash memory if possible.
Step 2 Use the ping exec command to send a message to the broadcast address
(255.255.255.255).
Step 3 If there is no response from the server, use the show arp exec command to look for
an entry in the ARP table that is associated with the server.
Step 4 Use the show ip route exec command to view the IP routing table. Look for an
entry in the table for the network or subnet of the server.
Sample Display:
The following is sample output from the show ip route command when entered
without an address:
Router# show ip route
Codes: I - IGRP derived, R - RIP derived, O - OSPF derived
C - connected, S - static, E - EGP derived, B - BGP derived
* - candidate default route, IA - OSPF inter area route
E1 - OSPF external type 1 route, E2 - OSPF external type 2
route
Gateway of last resort is 131.119.254.240 to network
129.140.0.0
O E2 150.150.0.0 [160/5] via 131.119.254.6, 0:01:00, Ethernet2
E 192.67.131.0 [200/128] via 131.119.254.244, 0:02:22,
Ethernet2
O E2 192.68.132.0 [160/5] via 131.119.254.6, 0:00:59, Ethernet2
O E2 130.130.0.0 [160/5] via 131.119.254.6, 0:00:59, Ethernet2
E 128.128.0.0 [200/128] via 131.119.254.244, 0:02:22,
Ethernet2
E 129.129.0.0 [200/129] via 131.119.254.240, 0:02:22,
Ethernet2
E 192.65.129.0 [200/128] via 131.119.254.244, 0:02:22,
Ethernet2
If a path to a boot server exists, a disconnected network is not the problem. If no
path exists, make sure that a path is available before again attempting to netboot.
TFTP server is down Step 1 Check the TFTP server to determine whether it is up and running. You can do this
by attempting to make a TFTP connection from the boot server to itself. The
connection will be successful if the TFTP server is running.
Step 2 If the TFTP server is not running, initialize it. The initialization process will vary
depending on the type of boot server.
For a BSD UNIX server, check the /etc/inetd.conf file. If the TFTP server is not
included in this file, add the appropriate line and cause inetd to reload its
configuration.
Router image in
wrong directory
Step 1 Look at the server configuration file to see whether it points to the directory in
which the router image is located.
Step 2 Move the router image to the correct directory if necessary.
Step 3 Make sure the /tftpboot directory is reachable over the network.
Router system image
file permissions are
incorrect
Step 1 Check the permissions of the system image file.
Step 2 If necessary, change the permissions for the file. On a UNIX boot server, set the
permissions for the file to owner read/write, group read, and global read (the UNIX
command for setting these permissions is chmod 644 filename).
Bad protocol address
Step 1 Check the server configuration file to make sure the IP address of the host is
correct.
Step 2 Change the configuration if it is incorrect.