Juniper JNCIA JN0-103 – Operational Monitoring and Maintenance
- System and Chassis Information
Welcome back. In this lecture, we’ll understand how can we use Show commands to view important system and chassis information. Let’s begin. First, let’s talk about system information. We can use the operational mode Show System command to get system information. I have some important Show System commands listed on the screen right now, such as Show system alarms, shows boot messages, show System commit, showstem connections, show system login lockout, memory storage, uptime users, and so on. The best way to understand this is by getting to the terminal. Let’s go there and take a look at the commands. All right, I’ve logged into a terminal. Let’s start trying the commands one by one. So I’m going to do showsystem and let’s start with a question mark first. The first one that we’ll look at is alarms. Show system alarms. Right now there are no alarms on my system, which is very good. We can also look at Show System boot messages.
This command can be used to look at the boot messages that were generated when you rebooted the device. Let’s do that. Show system boot messages. You will see there’s so many messages starting from here, you have all these boot messages. If you had any problems while booting the device, this is a good way to find out. By looking at the boot messages. I’m going to do a control C to exit out and hit the Apparo. Do a control W to erase the word on the left. And let’s do a question mark. The next command we’ll look at is Show System commit. This is a very handy command. This command will show you the history of all the commit operations that were performed on the device. Let’s try that. Show system commit. Starting from commit zero all the way up to commit 49. You have the history along with the timestamp and the person who committed the changes. In one of the earlier lectures, we talked about the number of rollback configurations that can be stored on the device.
I remember setting the value as 50. And you see that over here we have commit zero to commit 49. We also looked at rescue configuration, which can be used to roll back, which can be rolled back to restore connectivity. You have the rescue configuration here as well. Let’s try one more show System mark. Connections is a very good option. Show system connections. It will show you the list of open ports and established connections. Let’s try that show System connections. There you go. So you have the protocol on the left hand side. You have the local IP address, which is the IP address of the Juno’s device. Notice that it is a combination of IP address and port number. And you have the for an IP address or the remote IP address with which the connection has been established. And you can see the state of the connection. Established means the session has been established or the connection has been established. Listen basically means the port is open. It is waiting for a connection.
If you wanted to get detailed information about the connections, what we can do is we can say Show System connections and we can use the word extensive. This will give you more information about every connection. Let’s try that. There you go. For every connection that has been established, you get some more information over here. So if you’re troubleshooting, this could be handy. I’ll do the Control C and hit the Apparo. Going to delete these two words. Let’s do showsystem, question mark. Showsystem License is a good option to check all the license modules. Let’s try that. Show system license. And you can see the licenses that have been installed on the device. The next one is very useful, show System Login. And you have to follow that up with lockout. Show system login lockout. It will show you all the users who have been locked out. Let’s do that. Show system login lockout. You’ll notice so many users have been locked out. Remember one of those earlier lectures where I was showing you the log files and there was a lot of login attempts coming from outside. I had showed you some log entries as well that showed failed login attempts. I have a lockhart policy configured on my device. If you try the incorrect password a certain number of times, your account gets locked out. You’ll notice over here there’s a constant attempt to break the device’s password.
The attempt is to use common user names. For example, you can see that over here. FTP user support. One, two, three. Administrator Anonymous test. Yabuntu admin. Some of them are really funny. Music bot mother Demon Right. So this is a good way to find out all the locked out users. It’s kind of funny the way they’re constantly trying to break the password. All right, let’s exit out. Let’s do a control C. Let’s try show system user question mark. Show system memory. Again, a very useful command from a troubleshooting perspective. It will show you the memory utilization of your device. Let’s try that. You can see the total memory, the reserved memory, the free memory, and the memory that has been taken by every process. So if you are seeing high memory utilization on your device, and you want to find out which process is responsible for that, you can use this command. Show system memory. One more command which is very useful. It’s called a show system processes. It will show you the list of all the processes that are running on your device. Let’s try that.
You see, that the list of all the running processes. Also known as demons, or some people call it as daemons. Right? Okay, control C. Let’s try some more commands. Show system mark. Showsystem reboot is a very useful command. It shows you any pending reboots on the device. So right now it says there is no schedule shutdown or reboot. We can also check out the storage statistics of the device using the command Show System Storage, hit Enter. You can see how much is the free capacity available on the device. This is a very handy command, especially when your storage starts filling up with a lot of log entries and files that have been created on the device you can use this command to find out how much of storage is still available. Another command which is very useful is called as Show System Uptime. Let’s try that. There you go.
So it can be used to find out what’s the current time on the system, when was the system rebooted? When were the protocol started? This is very handy, guys, especially if you are in a setup where there are multiple users who are configuring the device. This information can be very handy. When was the device last configured and who made the changes? It’s a very useful command and you can also see how many users are logged in right now and what’s the load on your device right now. It also shows you the uptime of the device. One last command we can do show System Users. To find out which users are logged into the device right now. Let’s try that show. System Users And right now it’s only me who’s logged into the device. So we’ve seen a bunch of useful Show stem commands.
There’s so much of information in that in troubleshooting scenarios, this information can help you immensely. All right, back over here. Let’s now understand how to view chassis information. The command to do that is Show Chassis. I have listed some important commands like show chassis alarms, show chassis environment, show chassis hardware, and show chassis routing options. Let’s try these on the device back over here, let’s start trying the commands one by one. So I’m going to do show chassis question mark. The first one is. Alarms hit enter. Right now I don’t have any chassis alarms, which is very good. We could also try Show Chassis Cluster in case your device is a part of a cluster. My device right now is a standalone device, so this command is not applicable. Show System Environment can be used to view status and temperature information. Let’s try that. Show system environment. There you go. You can see the routing engine status and the power supply status and the temperature over here show System Hardware. Very good command.
Or show chassis hardware. I believe I said this one wrong as well. It’s not show system environment. It’s show chassis environment. Let’s try show chassis hardware. This is a very interesting command. It gives you information about the chassis and the routing engine serial number. What’s the model of the device? You can see that over here, I have only one FPC called FPC zero. And inside that I have only one Pic, which is Pic zero. Now, Pig zero has eight fast Ethernet interfaces.
So if you’re not sure how many FPCs and how many Pics you have on the device. You can do Show chassis hardware. So my SRX 100 B has a total of nine interfaces, one for console and eight fast ethernet interfaces. Finally, let’s take a look at Show chassis routing engine. That will give you more information about the routing engine like the temperature, the memory utilization, the CPU utilization and so on. Alright, so that’s all the topics for this lecture. I hope you found it interesting. In the next lecture we’ll talk about interface monitoring. I’d like to thank you for watching and I’m going to catch you in the next lecture. Thank you.
- Interface Monitoring
Welcome back. This is a short lecture on interface monitoring. Let’s begin. In this lecture, we’ll see the different commands that can be used to view interface information on a Juno’s device. To take a look at this, let’s go to the terminal. Okay, I’m at the terminal. Let’s try the commands one by one. The most basic command that you can try is is show interfaces. Show interfaces hit enter. You’ll get data about all the interfaces on your device. For example, you can see over here I have data about feed. So you get data about all the interfaces, which is a lot of data. Let’s say you wanted to view data only about a specific interface. So we can do this. We can say show interfaces dot zero, hit Enter. Now we can view information about a specific interface.
One more command which is very handy for troubleshooting purposes is show interfaces TERS. Let’s try that. Show interfaces TERS. Hit enter and you’ll see a summarized view of all the interfaces. You’ll see the interface names on the left hand side. You then have the administrative status, the link status, the protocol, and the local IP address. The administrative status indicates if the device has been hard coded as up or down. The status called up means the interface has been enabled. If you see down, that means the interface has been shut down. The link status over here indicates if the interface is receiving signals or not. For example, this interface is physically up, but it is not receiving any signals. This one is the protocol and you have the IP address over here.
You can actually filter this down. For example, let’s say I only wanted to know about fast ethernet interfaces so I could do something like this show interfaces fe zero zero. I can do a Star over here and I can say terse that will only match the fast ethernet interfaces. If I only wanted to view fast ethernet unit zero, I could do this. Just hit the up arrow and I’m going to change this command to show interfaces fer zero terse. That would only show me the unit zero portion of every fast ethernet interface. You see how flexible this is? And this is why I love Juno’s. This is one of those devices which makes you feel so comfortable. It is so easy to learn, it is so easy to work with. Let’s also try this show interfaces. I’m going to say Fe 0010 and we can also do extensive. If you need all possible information, try extensive. It will give you all possible information.
There’s also one more command that you can try that is show interfaces detail which gives you quite a lot of information, but a little less compared to extensive. We can try that as well over here, extensive detail. These are commands which are very handy, especially when you are troubleshooting. We also have one more command which is called as monitor traffic command which allows you to monitor the traffic on your device in real time. Let’s try that. I’m going to say monitor first. We’ll do a question mark. There’s an option at the bottom which says traffic. Let’s try that. Monitor traffic, question mark. We can actually do an Enter over here. Let’s try that. And you’ll notice that it gives you traffic in real time, all the traffic that is coming onto your device, right? Just turn it away.
We can also do this monitor interface traffic which gives you live traffic information about your device. So I’m just going to do Enter and you’ll notice I have live information about my interfaces. For example, you can see over here for fast ethernet zero, the input packets, the output packets for Fe one, which is my inside interface, you have input and output packets and you can see that they are changing on the fly to exit out. We can do Q or CTRL C. All right? And if you wanted to monitor a specific interface, we could do that as well. So monitor interface and we can say Fe zero slash zero one, hit Enter.
Now we are monitoring only a specific interface. You can see some information over here, the interface name, the link status, the encapsulation, the speed of the interface and some statistics over here, right? So these can be very useful commands, especially in troubleshooting scenarios. Just do a control C to exit out and let’s go back to the slides. All right, so that’s the little topic on interface monitoring. In the next lecture we’ll look at some of the network utilities that are available on a Juno’s device. I’d like to thank you watching and I’m going to catch you in the next lecture. Thank you.