Do commands effect a router immediately

datchcha

When you modify the running configuration (RAM) does it affect the router immediately, or do you have to save to startup configuration (NVRAM) and reload the router?

Netstudent

immediately....NVRAM is there so that the changes that immediately affect the router can be loaded in case of a reload of power down. When I setup my labs at home I rarely do a copy run start. I do a copy run tftp just in case I want to save my work. But usually I like to tear down and setup each lab from scratch just to get the pratice.

datchcha

Netstudent wrote:

immediately....NVRAM is there so that the changes that immediately affect the router can be loaded in case of a reload of power down. When I setup my labs at home I rarely do a copy run start. I do a copy run tftp just in case I want to save my work. But usaaly I like to tear down and setup each lab from scratch just to get the pratice.

Understand thank you for the help. One more question just to make sure i am on the right page - switches work the same way right?

Netstudent

yes sir

calaverasgrandes

Its actually a pretty good question. If I hadnt taken the plunge and bought some routers to play with I'd be stumped. Just in case anyone is womdering. It isnt expensive, I got several routers, and dint spend more than $30 on any one of them. Now I just have to start doing things that I am not comfortable with (like ACLs and such)

wait2dominate

calaverasgrandes wrote:

Its actually a pretty good question. If I hadnt taken the plunge and bought some routers to play with I'd be stumped. Just in case anyone is womdering. It isnt expensive, I got several routers, and dint spend more than $30 on any one of them. Now I just have to start doing things that I am not comfortable with (like ACLs and such)

I plan on doing just that for ACL practice....and you have anice range of things to try to block if you want, as for as port 80 goes.....google, yahoo, etc, etc.

datchcha

No the reason why i asked this questions - is because i had a MCSE tell me that "oh, no...you can't modify a switch, nor router during production hours, because you have to reboot the device." I believe he was using the web interface, and it asks to reload the page, but not sure. I only live by the CLI.

thank you all for your help.

Stotic

That only commands I know that don't take place immediately are VLAN Database commands that aren't applied until you exit VLAN Database mode.

dtlokee

There are a few commands that require a reload but you're not going to use them during normal system management. These include setting the system mtu, changing the sdm template, coverting to multiple context mode on an ASA and so on. These are things that would typically be done before a device is put into production. There are some commands that don't have an effect until you exit out of a mode (like configuring MST) or until you enter other commands (like creating an access list without applyinh it to an interface)

As any engineer knows when making a configuration change, hitting the enter key, then having the terminal session go dead (because you've just killed it with the configuration change) most commands happen immediately.