Use the Configure Replace command to speed up your labbing
- command line |
- Cisco |
- CCIE
I've been labbing quite a bit lately, working on Narbik's R&S workbooks, and I've been rebooting my rack after nearly every lab to clear things out. Well, I was perusing the Interwebs and a forum post reminded me of the config replace command. Sheesh! I wish I would have remembered that a few hundred reboots ago...
Even though I knew about this command, and have even included it in a blog post or two in the past, I had forgotten about it since I wasn't using it all that often. So, just in case someone else out there has forgotten about it, I figured I'd do a quick write up demonstrating the command in action and hopefully jostle some memories (or just help me remember if I forget it again).
Here is a 1841 router that used to be R5, but I changed it's hostname to Testing and did a no shutdown on all it's interfaces. Follow the config below for the usage:
Testing(config-if)#end Testing#show ip int bri Interface IP-Address OK? Method Status Protocol FastEthernet0/0 unassigned YES NVRAM up up FastEthernet0/1 10.1.2.3 YES manual up up Serial0/0/0 unassigned YES NVRAM up up Serial0/1/0 unassigned YES NVRAM down down SSLVPN-VIF0 unassigned NO unset up up Testing# *Jan 16 03:18:28.327: %SYS-5-CONFIG_I: Configured from console by console Testing# Testing# Testing#configure replace nvram:startup-config This will apply all necessary additions and deletions to replace the current running configuration with the contents of the specified configuration file, which is assumed to be a complete configuration, not a partial configuration. Enter Y if you are sure you want to proceed. ? [no]: yes Total number of passes: 1 Rollback Done
Notice the Hostname changes back to R5 and the interfaces all drop after typing Yes to proceed.
R5# *Jan 16 03:18:50.379: Rollback:Acquired Configuration lock. *Jan 16 03:18:52.119: %PARSER-6-EXPOSEDLOCKRELEASED: Exclusive configuration lock
released from terminal '0' -Process= "Exec", ipl= 0, pid= 3 *Jan 16 03:18:52.539: %LINK-5-CHANGED: Interface Serial0/1/0, changed state to administratively down *Jan 16 03:18:53.287: %LINK-5-CHANGED: Interface FastEthernet0/0, changed state to administratively down *Jan 16 03:18:53.295: %LINK-5-CHANGED: Interface FastEthernet0/1, changed state to administratively down *Jan 16 03:18:53.315: %LINK-5-CHANGED: Interface Serial0/0/0, changed state to administratively down R5# *Jan 16 03:18:54.287: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down *Jan 16 03:18:54.295: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down *Jan 16 03:18:54.315: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to down R5#show ip int bri Interface IP-Address OK? Method Status Protocol FastEthernet0/0 unassigned YES NVRAM administratively down down FastEthernet0/1 unassigned YES manual administratively down down Serial0/0/0 unassigned YES NVRAM administratively down down Serial0/1/0 unassigned YES NVRAM administratively down down SSLVPN-VIF0 unassigned NO unset up up R5#
Couldn't be simpler! Now if only there was a simple way to keep from forgetting things...
Comments
Juniper replace command
Juniper have a similar replace command, that replace a specific pattern, it seems better.
So, if you are studying for
So, if you are studying for your JNCIE you can save time while labbing too ;)
Juniper
It is easier to use the rollback function (depends on the rollback count you have on the device) or save a rescue config before you start.
is it available on the ASA
is it available on the ASA
Doesn't look like it...
I just checked an ASA running 8.4 and didn't see this command.
asa(config)# configure ? configure mode commands/options: WORD Configure from HTTP: http(s)://[:@][:]/.
Place IPv6 address within square brackets if a port is
specified.
factory-default Configure from factory-default
memory Configure from memory
net Configure from tftp
exec mode commands/options:
terminal Configure using terminal/console
Also, you probably don't want to use the configure memory command. There might be a corner case where you need to merge the startup-config and the running-config, but in my experience, it just ruins a good running-config and causes a traffic interruption.
Replace Command
Been doing this with my home CCIE lab but Switches dont always like this command....
Brocade
The company I work for is pretty much arrested to Brocade because that is our network. I am curious does Brocade have a similar command to this as Cisco?
what if it is? # copy start
what if it is?
# copy start run
does it produce the same result?
Merge rather than replace
Copy start run does not produce the same results as the config replace command. Copy start run would merge the startup-config with the running-config. This would likely produce undesired results in a production environment.
why R5 and not Router?
If this is supposed to produce a fresh "blank" config file then why does it show R5 instead of the default "Router"?
Thanks Kevin
TIA
I know this is and older
I know this is and older thread but I don't think it produces a blank config. It just replaces the running config with the startup config. That way you can change the running config all you want and as long as you don't write mem or copy run start you can go back to exactly what you had without rebooting the router.