Lab 3: Upgrading the IOS and Restoring a Configuration from a TFTP Server-Part II

Lab 3: Upgrading the IOS and Restoring a Configuration from a TFTP Server ”Part II

Lab Walkthrough

The first step in this lab is to configure all the equipment as shown in Figure 1-16. Also attach a workstation to the same physical segment. When all the devices can ping each other, you can move on.

This lab introduces another new concept ”making the router function as a TFTP server. To make a router perform as a TFTP server, add the command tftp-server [ flash rom ] filename from configuration mode. In Example 1-44, first you perform a show flash command to view the files available on Flash memory (be sure to note the filename). From the configuration mode, enter the command tftp-server flash filename. To avoid typing mistakes, which is a common problem on Flash upgrades, use cut-and-paste techniques for the filename.

Example 1-44 Making a Router Serve as a TFTP Server

 ufo# ufo#  show flash  System flash directory: File  Length   Name/status   1   8102652  c2500-js-l_112-16.bin [8102716 bytes used, 285892 available, 8388608 total] 8192K bytes of processor board System flash (Read ONLY) ufo#  conf t  Enter configuration commands, one per line.  End with CNTL/Z. ufo(config)#  tftp-server flash c2500-js-l_112-16.bin  ufo(config)#  ^Z  ufo# 

Moving over to rosewell, you can now upgrade the IOS through TFTP on router ufo. To perform this task, use the copy tftp flash command, and answer the questions accordingly . Use ufo as the TFTP server, and use c2500-js-l_112-16.bin as the filename. Example 1-45 demonstrates the upgrade of rosewell from ufo.

Example 1-45 Upgrading the IOS by Using TFTP

 rosewell#  rosewell#    copy tftp flash     Copying from the server to the router  ****  NOTICE  **** Flash load helper v1.0 This process will accept the copy options and then terminate the current system image to use the ROM based image for the copy. Routing functionality will not be available during that time. If you are logged in via telnet, this connection will terminate. Users with console access can see the results of the copy operation.                          ---- ******** ---- Proceed? [confirm]  y  System flash directory: File  Length   Name/status   1   8034308  c2500-js-l_112-11.bin [8034372 bytes used, 8742844 available, 16777216 total] Address or name of remote host [255.255.255.255]?  172.16.16.2  Source file name? c2500-js-l_112-16.bin Destination file name [c2500-js-l_112-16.bin]?  c2500-js-l_112-16.bin  Accessing file 'c2500-js-l_112-16.bin' on 172.16.16.2... Loading c2500-js-l_112-16.bin .from 172.16.16.2 (via Ethernet0): ! [OK] Erase flash device before writing? [confirm]  y  Flash contains files. Are you sure you want to erase? [confirm]  y  Copy 'c2500-js-l_112-16.bin' from server   as 'c2500-js-l_112-16.bin' into Flash WITH erase? [yes/no]  yes  00:01:15: %SYS-5-RELOAD: Reload requested  the router reloads SERVICE_MODULE(1): self test finished: Passed %SYS-4-CONFIG_NEWER: Configurations from version 11.2 may not be correctly under stood. %FLH: c2500-js-l_112-16.bin from 172.16.16.2 to flash ... System flash directory: File  Length   Name/status   1   8034308  c2500-js-l_112-11.bin [8034372 bytes used, 8742844 available, 16777216 total] Accessing file 'c2500-js-l_112-16.bin' on 172.16.16.2... Loading c2500-js-l_112-16.bin .from 172.16.16.2 (via Ethernet0): ! [OK] Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee  ee ...erased  Flash is erased  Loading c2500-js-l_112-16.bin from 172.16.16.2 (via Ethernet0): !!!!!!!!!!!!!!!! <<<text omitted>>> !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! [OK - 8102652/16777216 bytes] Verifying checksum...  OK (0x8DCB) Flash copy took 0:04:40 [hh:mm:ss] %FLH: Re-booting system after download F3: 8004052+98568+315656 at 0x3000060 <<<text omitted>>> 00:00:23: %SYS-5-RESTART: System restarted -- Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JS-L), Version 11.2(16), RELEASE SOFTWARE (fc1) Copyright (c) 1986-1998 by cisco Systems, Inc. Compiled Tue 06-Oct-98 11:54 by ashah rosewell>show flash System flash directory: File  Length   Name/status  1   8102652  c2500-js-l_112-16.bin  New IOS  [8102716 bytes used, 8674500 available, 16777216 total] 16384K bytes of processor board System flash (Read ONLY) rosewell> 

After the Flash download, the router verifies the checksum of the file before reloading. At the end of the example, you perform a show flash command to verify that the new IOS is place.

The second part of the lab requires you to copy the startup-configuration from the router ufo, modify it by changing the hostname to w-balloon, and then copy it back to its original location. To accomplish this, you use the copy startup-config tftp command and follow the prompts. Before you do this, it is always a good idea to ensure that the router can ping the TFTP server. Example 1-46 demonstrates the use of the ping and copy commands.

Example 1-46 Copying the startup-config to a TFTP Server

 ufo#  ping 172.16.16.254  Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.16.254, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms ufo#  copy startup-config tftp  Remote host []?  172.16.16.254  Name of configuration file to write [ufo-confg]?  ---- carriage return Write file ufo-confg on host 172.16.16.254? [confirm]  y  Writing ufo-confg !! [OK] ufo# 

It is important to note that, as its name implies, TFTP is trivial. That means that TFTP has no way of overwriting files or prompting the user for input after the copy process begins. If you tried this same procedure again, you would get an error because the file already exists from your first copy. You might or might not experience this error; some versions of TFTP have options that automatically overwrite the existing file if it exists. Example 1-47 demonstrates the error when a duplicate file is found and cannot be overwritten.

Example 1-47 TFTP Copy Error, Duplicate File Found

 ufo#  copy startup-config tftp  Remote host []?  172.16.16.254  Name of configuration file to write [ufo-confg]?  ---- return Write file ufo-confg on host 172.16.16.254? [confirm]  y  Writing ufo-confg TFTP: error code 0 received - File exists  [Failed] ufo# 

When the file is successfully copied to your PC, use Microsoft Wordpad to edit it. Locate the HOSTNAME field and change ufo to w-balloon. Finally, copy the file back to the router by using the copy tftp startup-config command. When the file is copied back to the router, you might want to view it; this can be done using the show startup-config command. To activate the new configuration, either reload the router or perform the copy startup-config running-config command. When this is done, the host name should be changed from ufo to w-balloon. Example 1-48 demonstrates this process.

Example 1-48 Copy Configurations from a TFTP Server

 ufo#  copy tftp startup-config  Address of remote host [255.255.255.255]?  172.16.16.254  Name of configuration file [ufo-confg]? Configure using ufo-confg from 172.16.16.254? [confirm]  y  Loading ufo-confg from 172.16.16.254 (via Ethernet0): ! [OK - 564/32723 bytes] [OK] ufo# %SYS-5-CONFIG_NV: Non-volatile store configured from ufo-confg by console tftp f rom 172.16.16.254 ufo#  show startup-config  Using 564 out of 32762 bytes ! version 11.2 no service password-encryption no service udp-small-servers no service tcp-small-servers ! hostname W-BALLOON ! interface Ethernet0  ip address 172.16.16.2 255.255.255.0  no ip route-cache  no ip mroute-cache ! interface Serial0  no ip address  no ip route-cache  no ip mroute-cache ! interface Serial1  no ip address ufo#