Transcription: So we’ve been told that we need to recover the passwords on these devices. Let’s start with router 1. Here’s Router 1, we can see some neighbour relationships have come up. So EIGRP neighbour relationships have been formed, type enable, don’t know what the password is. So there’s not much we can do here. We can’t reload the router. For password recovery, you need physical access. So on the router, I’m going to turn off the power and then turn it on again and then I’m going to press control C which works as a control break on my keyboard. The break sequence depends on your keyboard and operating system such as Windows or Mac and the application that you’re using. So on Windows you could use putty, could use teraterm or some other terminal emulation software. You’ll have to look at what are the break sequence is on that specific device. So have a look on your keyboard for a breaker key and press control break as an example or control C to break the startup process. Question mark enter shows us various options available in ROM or ROM monitor mode help also gives us the same list of commands. We going to bypass the startup configuration by setting the configuration register to 0x2142. You can find a list of configuration register values by doing a search on Google. Just search for Cisco configuration register and you’ll find documents such as the following that allow you to see various configuration register values. 0x2142 allows you to ignore the startup configuration. In other words the router ignores NVRAM and boots without a startup configuration. I’ll then reset the device to get it to reboot. So that’s router 1. Router 2 has a similar problem. When I type enable, I don’t know the password of router 2. Now before I restore the password on router 2, let’s complete router 1 because it’s now booted up. I’ll use node to bypass the initial configuration dialog. I now have a router using a default configuration. Type enable. This router has a default configuration. But notice the startup configuration shows me the enable password that is shown in clear text. So we would know that password here but you can bypass that even if you don’t know what the password is. Notice we are currently in enable mode. So again, the startup configuration shows us the password but that’s because service password encryption has not been set. If that was set, I wouldn’t know what the password was but I could still restore the routers’ configuration by using the command copy startup-configuration running-configuration show run now shows us the configuration including the password but notice loopback addresses and physical interface addresses are now configured on the router. If service password encryption was set, I wouldn’t know what the password was but I could still restore the configuration. You can hack this password but notice on devices such as Router 2 and Switch 1 that are using this secret password, you will not easily able to work out what the password is. But we can still bypass the configuration and then set the enable password to Cisco. So even if I don’t know what the password is, I can bypass the device configuration by setting the configuration register to 0x2142 rebooting the router and then going to privilege mode or enable mode and then copying the configuration and then setting the password. One thing to be aware is notice the physical interfaces are shut down. So even though you restore the configuration, you need to go and no shut the physical interfaces. Once you’ve done that restore. so show ip interface brief notice the interfaces are now up and I can see the router configuration by using the wr command or in the exam, copy running-config, startup-config. So now, if exit out of the router and then go back in. Type enable. The password used now is cisco. I’ve encrypted that password. But if I have not encrypted the password, this will be displayed in clear text. In the exam, do what you’re told. Don’t do extra things like I’m doing here. Do what’s required. I’m trying to show you extra options and teach you various options on the routers. Now just be careful even though we’ve saved the configuration and we can log back into the router, the running configuration doesn’t affect the configuration register. I need to configure the configuration register. So I will set that to 2102. So show version shows us that the configuration register will be set to this at the next reload. The configuration register is separate to the running configuration. So even though you’ve saved the running configuration, it doesn’t change the configuration register. The configuration register needs to be set separately. So that’s Router 1 completed. Let’s have a look at Router 2. Packet Tracer file: goo.gl/zR1bYq Discounted link to course here: goo.gl/aXVKbf #ccna #ccent #cisco
Hi, does anyone know how to break 0:49 on MacOS using Packet Tracer? I've tried (Ctrl + C, Ctrl + Shift + C, Cmd + C) nothing works. I also haven't seen the setting to see the keyboard shortcut mappings and how change a certain shortcut. This is making me go insane. Can anyone please help? Thank you.
Hi David, I have 4 Switches of Cisco SG550XG-24F Stacked together, I lost the password, if I need to preform the password recovery, can I do it on the master only and that will get the job done or do I need to disconnect them all and preform on each switch? Thank you in advance, any info would greatly appreciated.
Transcription:
So we’ve been told that we need to recover the passwords on these devices.
Let’s start with router 1.
Here’s Router 1, we can see some neighbour relationships have come up.
So EIGRP neighbour relationships have been formed, type enable, don’t know what the password is.
So there’s not much we can do here. We can’t reload the router. For password recovery, you need physical access. So on the router, I’m going to turn off the power and then turn it on again and then I’m going to press control C which works as a control break on my keyboard. The break sequence depends on your keyboard and operating system such as Windows or Mac and the application that you’re using.
So on Windows you could use putty, could use teraterm or some other terminal emulation software.
You’ll have to look at what are the break sequence is on that specific device.
So have a look on your keyboard for a breaker key and press control break as an example or control C to break the startup process.
Question mark enter shows us various options available in ROM or ROM monitor mode help also gives us the same list of commands.
We going to bypass the startup configuration by setting the configuration register to 0x2142.
You can find a list of configuration register values by doing a search on Google. Just search for Cisco configuration register and you’ll find documents such as the following that allow you to see various configuration register values.
0x2142 allows you to ignore the startup configuration. In other words the router ignores NVRAM and boots without a startup configuration. I’ll then reset the device to get it to reboot. So that’s router 1.
Router 2 has a similar problem. When I type enable, I don’t know the password of router 2.
Now before I restore the password on router 2, let’s complete router 1 because it’s now booted up. I’ll use node to bypass the initial configuration dialog. I now have a router using a default configuration.
Type enable. This router has a default configuration. But notice the startup configuration shows me the enable password that is shown in clear text.
So we would know that password here but you can bypass that even if you don’t know what the password is. Notice we are currently in enable mode.
So again, the startup configuration shows us the password but that’s because service password encryption has not been set. If that was set, I wouldn’t know what the password was but I could still restore the routers’ configuration by using the command copy startup-configuration running-configuration
show run
now shows us the configuration including the password but notice loopback addresses and physical interface addresses are now configured on the router. If service password encryption was set, I wouldn’t know what the password was but I could still restore the configuration.
You can hack this password but notice on devices such as Router 2 and Switch 1 that are using this secret password, you will not easily able to work out what the password is. But we can still bypass the configuration and then set the enable password to Cisco.
So even if I don’t know what the password is, I can bypass the device configuration by setting the configuration register to 0x2142 rebooting the router and then going to privilege mode or enable mode and then copying the configuration and then setting the password.
One thing to be aware is notice the physical interfaces are shut down. So even though you restore the configuration, you need to go and no shut the physical interfaces. Once you’ve done that restore.
so show ip interface brief
notice the interfaces are now up and I can see the router configuration by using the wr command or in the exam, copy running-config, startup-config.
So now, if exit out of the router and then go back in. Type enable. The password used now is cisco. I’ve encrypted that password. But if I have not encrypted the password, this will be displayed in clear text.
In the exam, do what you’re told. Don’t do extra things like I’m doing here. Do what’s required. I’m trying to show you extra options and teach you various options on the routers. Now just be careful even though we’ve saved the configuration and we can log back into the router, the running configuration doesn’t affect the configuration register. I need to configure the configuration register. So I will set that to 2102.
So show version
shows us that the configuration register will be set to this at the next reload. The configuration register is separate to the running configuration. So even though you’ve saved the running configuration, it doesn’t change the configuration register. The configuration register needs to be set separately.
So that’s Router 1 completed. Let’s have a look at Router 2.
Packet Tracer file: goo.gl/zR1bYq
Discounted link to course here: goo.gl/aXVKbf
#ccna
#ccent
#cisco
Thank you a Billion times David
Thank you Arbër
very good. David. very useful.
Thank you!
Hi, does anyone know how to break 0:49 on MacOS using Packet Tracer? I've tried (Ctrl + C, Ctrl + Shift + C, Cmd + C) nothing works.
I also haven't seen the setting to see the keyboard shortcut mappings and how change a certain shortcut. This is making me go insane. Can anyone please help? Thank you.
what about switch
Hi David, I have 4 Switches of Cisco SG550XG-24F Stacked together, I lost the password, if I need to preform the password recovery, can I do it on the master only and that will get the job done or do I need to disconnect them all and preform on each switch? Thank you in advance, any info would greatly appreciated.
Where is the switch recovery tutorial?