System information

Troubleshooting Booting Problems
Book Title
3-50
Table 3-15 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 3-15 Booting: Timeouts and Out-of-Order Packets Prevent Netbooting
Booting: Invalid Routes Prevent Netbooting
Symptom: Invalid routes prevent successful netbooting. If the router is sending packets over an
invalid path, a message similar to one of the following is displayed on the console:
Booting gs3-bfx!OOOO..........[timed out]
Booting gs3-bfx!.O.O.O.O..........[timed out]
Booting gs3-bfx!!!!!!!!!!OOOOOOOOOO..........[timed out]
In some cases, there might be an initial response from a server but the netboot sequence still fails.
The boot message would be similar to the following:
Booting gs3-bfx!..........[failed]
Table 3-16 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 3-16 Booting: Invalid Routes Prevent Netbooting
Possible Problem Solution
Link is saturated
Step 1 Boot the router from ROM and ping the TFTP server. Determine whether
timeouts and out-of-order packets appear.
Step 2 Check local network concentrators for excessive collisions on the same
network. If there are excessive collisions, reorganizing your network topology
might help reduce collisions.
Step 3 Use the show interfaces exec command on routers in the path or place a
network analyzer between the router and server. Look for dropped packets and
output errors.
Step 4 If approximately 15% or more of the traffic is being dropped, or if any output
errors occur, congestion might be the problem.
Step 5 Wait until the traffic subsides before attempting to netboot the router. If the
problem is chronic, increase bandwidth or move the server closer to the router
being booted.
Link is down
Step 1 Check the continuity of the path from the booting router to the boot server
using ping or trace exec commands.
Step 2 If a break is found, restore the link and attempt to netboot again.