I have a 2511 Cisco router which I should downgrade it's IOS version to support IS-IS from c2500-is-l.123-26.bin to version c2500-js-l.122-24a.bin
when I used copy tftp flash command the router successfully reload and try to start the copy process, this copy process always failed.
I set the register value to 0x2101 to start in romom
I issued enable command
from this prompt no erase command is look like available
clear Reinitialization functions, type "clear ?" for list
configure Configure from terminal or over network
connect <host> Connect to host - same as typing just a host name
copy copy flash tftp or tftp flash
debug Enable debugging functions, type "debug ?" for list
disable Turn off privileged commands
disconnect <cn> Break the connection specified by name or number
enable Turn on privileged commands
exit, quit, logout Exit from the EXEC
name-connection Give a connection a logical name
ping Send echo messages
reload Halt and reload system
resume Make the named connection be current
setup Initialize system configuration
show <cmd> Information commands, type "show ?" for list
systat Show terminal lines and users
telnet <host> Connect to host using telnet protocol
terminal Change terminal's parameters, type "terminal ?"
test Run hardware tests, type "test ?"
trace <address> Trace route to <address>
undebug Disable debugging functions, type "undebug ?" for list
where Show open connections
which-route Display CLNS route table lookup
write Write configuration memory, type "write ?" for list
<cr> To resume connection
when I issued sh version command
3000 Bootstrap Software (IGS-RXBOOT), Version 9.14(9.b), MAINTENANCE INTERIM SOF
Patchlevel = 9.1(12.6)
Copyright (c) 1986-1995 by cisco Systems, Inc.
Compiled Fri 03-Feb-95 07:11 by chansen
System Bootstrap, Version 4.14(9.1), SOFTWARE
Router uptime is 42 minutes
System restarted by power-on
Running default software
cisco 2500 (68030) processor (revision C) with 16380K/2048K bytes of memory.
Processor board serial number 01760615
DDN X.25 software, Version 2.0, NET2 and BFE compliant.
1 Ethernet/IEEE 802.3 interface.
2 Serial network interfaces.
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Device not programmable)
Configuration register is 0x2101
I see device not programmable
if I tried copy tftp flash command I received : ERR: Device in READ-ONLY state
I was upgrade it's flash memory in the pass to a newer IOS software, now I need an older one version someone could help me ??