NOC Engineer interview questions | Network Engineering

[Applause] welcome back to my channel guys this your boy ali hope everybody's doing good it's been about a month i haven't made a video because i've been super busy with work and of course that's priority um this is just my side fun that i do and try to help people out answer some questions etc so my most recent video was about a life of a knock engineer and i got a lot of feedback and comments and stuff people asking me um you know how should they approach or prepare for an interview and uh you know so i did some homework and uh just gathered all my uh experience that i had with the interviews that i did for the noc engineering positions and back in my old days um this was about like 10 years back so i just wanted to like help you guys out maybe uh you know somebody who's uh trying to go for an interview and maybe this could help them out so when you go in for these knock interviews uh now nox stands for network operation center and this is where you work uh and pretty much monitor and troubleshoot all the network for the company or globally et cetera depends who you work for uh that you know the scope is different for each so but these uh questions that i'm about to address are going to apply to level 1 level 2 level 3 and even higher than that so um you know i mean if you if you are going for an interview um i think this would be a really really good guide and i think if you just hit this video and go for your interview i think you'll probably do really well enough to get a job and uh and and that's uh that's my my two cents about that now when you do go for an interview make sure you do prepare a little bit obviously you know preparing as in be like you know be confident you know and stuff like that the basic stuff that they ask you you know about your career and your work experience and why do you want to work for the company and stuff like that but make sure you do understand how to troubleshoot things because when you work in a knock i think the number one thing that they're really trying to find out is that if you have the troubleshooting mindset because they could hire any straight out of school person with no experience and just train them how to disable alarms or check alarms and stuff like that but but what the noc engineers really get paid for is is how they troubleshoot right so let's say if a gateway or a site does go down how do you proceed right how do you what's your step one what's your step two how do you they want to they want to know how you what's your thinking process behind troubleshooting now you know in my case i would always try to replicate the problem in like a sandbox environment um so if i could replicate it most likely i could you know keep working on it and uh you know i'll find a resolution but a lot of times problems are intermittent or sporadic so it's really really hard to catch them so then you have to run uh packet captures on gateways and stuff but that's besides the topic but i think the main thing they want to really know is that um your level of understanding of how you're going to proceed with troubleshooting because uh in my experience when i was working in the knock um you know a client would call and be like hey her network just went down and we're there managed services provider so i'm i'm in the knock and uh you know i would get an email or something or or maybe you know and then i would call the client up or they would call me and be like hey can you just help us out you know this and that so now these people who are calling you are senior management or middle management people and they're really responsible for bringing that network up in the shortest amount of time so what you have to do is pretty much jump on the call with them uh do a web conference uh so what i would do is send them a webex cisco webex or you could do zoom or whatever else screen share um so they would join the call and then it would be me maybe a couple other people on their team that are responsible for different stuff sometimes i don't have access so they have you know they give me access to log in and troubleshoot and stuff so now this could be very very nerve-wracking because um you know it's a down situation and the client could be losing a lot of money and you just have to kind of be at your a-game and be very comfortable and you have to be able to think under pressure and to be able to resolve the problem and and bring their network back up and and you know i've done this for so many years that i feel like um i've built that um thick skin uh where i'm comfortably able to do that uh if i had to back in my back when i was working in a knock uh so so yeah i mean i just wanted to share my experience with you guys so before we waste time let's jump right into it now of course the first thing i recommend you have you know down pack is the seven layers of the osi model model now what are the seven layers of course um i mean if you are applying for a noc engineer level position then you should know this without a doubt and i'll go through them right now so level one is physical then you got the data link and then you got the layer three is network and then you got the transport and then session presentation and application now most of your network stuff is on layer three and if you're doing a lot of you know mostly switching and and network stuff it's mostly um on the data link or or the network level which is layer two and three and sometimes it's rarely ever where you might have to send the client into their data center to make sure the cables are okay but that's like super rare so layer two layer three you're pretty much logging to these gateways and you know running packet analysis and traces and everything collecting logs and checking them and making sure the tcp and udp messages are sending what they're supposed to to server client and you know how the setup is according to the current infrastructure now this is just basic but like like if you work on databases and stuff they communicate on different levels and uh you know depending on what the problem is you have to know where to start troubleshooting so a lot of times if you don't know where to start you end up capturing wrong logs and then you're like sitting through those logs you're not going to find anything because obviously you didn't even capture the right ones and a lot of times these servers are not constantly logging so you have to make sure they're set to detail level of logging otherwise you're again not going to see anything because if you keep running detailed logs over and over all throughout the day and for forever you're obviously going to bog down the servers and you're going to bring everything down so you just have to make sure that you know you know what you're doing just make sure you are collecting the right ones because obviously um you know that's the key because once you collect the right traces it takes hours to be able to determine if the problem's there now a lot of times you might have to collect traces from from like five different places depends on where the packet ended up or where the packet dropped or whatever the case is right so um but the basics is that you have to be able to um collect the right traces but yeah know your osi model i mean seven layers they're without a doubt are gonna drill you down on that and uh of course network is you know all your protocols on the network level which is ip icmp ipsec igmp and packets how the packets work um data link which is your switching how the ethernet ppp switch so of course you know you're gonna they're gonna ask you can you tell me about yourself so here you want to talk about your strong points obviously you want to tell them a little bit about yourself you want to tell them your work experience that's related to the job you're applying for you don't want to go rambling about stuff that's unrelated or things you have done that doesn't relate to this job because that that will just simply disqualify you so you have to make sure when they ask you that question tell me about yourself you have to relate it to the current position that you're applying for so of course you got to know what a ping is right and why the ping command is used to check connectivity between a client and server and stuff like that so definitely that's going to be one of the questions so what is tcpip what is udp what is tcp what is the difference between them and they might ask you hey um you know which protocol is used if you're uh running packet analysis between these two um servers and you know what kind of messaging protocol are they using they might just ask you in in that sense as well um and then you know being being a team player is a huge part of working in a knock because um a lot of times you may run into depending on your company you know a lot of junior level engineers are going to come up to you at random times when you're busy and they're going to need guidance and and you have to help them out you have to actually walk walk over to their desk and kind of sit down with them and help them out so that's going to be a lot of mentorship you're going to have to do if you're on the escalation level but if you're on level 2 and you know you do need help you could go up to the seniors and go to the level three guys and they'll definitely help you out right so there's a lot of collaboration and and uh going back and forth and a lot of teamwork that you have to be a part of because not everybody knows everything but i'm sure somebody else does that sits next to you or something so constantly um you know you have to also show in the interview that you're a team player so they might ask you questions about what is a proxy and what what's the function of a proxy and why is a proxy used in certain network environments and stuff like that um you know so make sure you know what that is and they might they might throw uh like a case scenario where let's say a host computer cannot be reached over a local network using a host name but can be reached using an ip what do you think is a problem now in that case i mean it's a very basic level of um of of question i mean you have to know the answer for that it's normally something wrong with the dns right so you have to go check your c names other a aaa records and stuff like that you know they might ask you uh what is layer 3 what is layer 2 what is a network switch do um you know how do you what's the function of a network switch and they might ask you basic level stuff they might not like if you're depending on the level you're uh interviewing for like level three when i was applying for they would straight up ask you hey what command do you run if you wanna you know uh debug this this is on the gateway and you know so you have to know the commands but if you're going for level two then i think you know they might just ask you or level one that what is a network switch and stuff like that so make sure you know what that is and uh so how do you so how would you find uptime on a cisco router now that's one of the very basic thing i mean you could just do a run a show command and it'll tell you like if you do show version or there's a few other commands you can run once you're logged into um by telnet or ssh into the router on the version once you check that it'll tell you the version but it'll also tell you what's the uptime up time is pretty much how long the route has been up um and how many hours and minutes and so so that's a very basic question but they may ask you that so know that now they may ask you okay if you run into a problem where you cannot resolve a problem what would you do so then of course you would um you know try to get help from your peer or then you would escalate the problem and and of course they may ask you what is a three-way handshake so the client sends a synchronized request and then a server responds with a synchronized request and acknowledgement and then the client responds with the acknowledgement so it's in synack and then hack so that's how that works so you know know that they might ask you what is trunking now there's all kinds of trunking right all kinds of circuits trunks so you have to know what is trunking and what's the purpose for trunking and stuff like that now have you ever found yourself in a situation that required decision in which risk for failure was very high now what they're trying to really understand here is that you know how would you go about troubleshooting this and how would you go about you know gathering information about this and they want to know how would you logically or what's your thought process you would get into before you go ahead and start troubleshooting this type of thing so now now what you want to do is think out loud because they want to see how you're thinking what's your thought process so whatever you're gonna do just be like hey um so first you know if you need a no pad or a pen you could tell them and they would appreciate that because they know that you're really trying to answer the question in the best way possible so and of course uh you know if you have to take notes down to understand the questions and and give them a proper answer you're more than welcome to do that that's well uh that's welcomed into job interviews now they might ask you how would you test delay and route of packets between two connections um i mean you know trace route is one of the commands uh that you would you know constantly use and you're pretty much you know um using that you probably use that on cmd in windows is a similar command tracer t but you could you know you could use traceroute on the cisco cli as well to you know test connectivity between two endpoints so and how the you know route packets route back and forth and you could test delays and stuff so know that that's pretty basic too now how would you identify which pc and what port it's using on the network uh okay that's a good question so they might ask you hey how do you know how do you figure out what port you know that pc or or that workstation is on so you know you could look that up simply by using harp which is address resolution protocol and you know you could log into the switch and um pretty much get the mac address table from the switch so there's a couple of ways to do that but that might be a part of the question that they may ask as well now of course they're going to ask you now these are the technical questions that i just went over but they're going to ask you some behavioral questions and they might ask you why should we hire you and stuff like that now when when they ask you that um make sure you show them enthusiasm and you make sure you show them willing to learn um and if you don't know something tell them that you know you're a fast learner and if you are you know don't don't lie to them you know i would just be super honest because the thing is like if you do end up getting the job maybe you won't like it or maybe something bad will happen at that job if you're trying to bluff it through the interview so make sure you know all these questions that i'm telling you i'm just not telling you so you could go ahead and try to you know beat around the bush and get through the interview but actually go and study these things right because that might be part of what you really need to do day to day in your production level network so you know but yeah i mean why should we hire you that's a great question so make sure you have a really um outstanding answer for that that you know but but yeah i mean um so these are pretty much um just some basic questions that i came up with that were asked in my days um now it's been about 10 years so these are you know these are still relevant because um people who are trying to get into the network field or you know like myself i started in in the knock on level two and then work my way up so now i'm completely different i'm doing a lot of um like pre-sale stuff and design and solution architecture and everything but that took a lot of years to be able to understand the back end of things so so either way um guys if you haven't subscribed you know hit the subscribe button if this video was any help to you um let me know in comments and if you have any questions do drop in the comments i i normally answer like all the comments uh hit the bell icon subscribe to my channel tell your friends about it and i will see you guys in a bit

Channel: Ali MK Raja

Views: 6,083

Keywords: Network, CCIE, Cisco, Netgear, Router, Switch, NSX, Asus, Juniper, Palo Alto, Cisco Networks, Cisco Certified Internetwork Expert, Unified Communication, Voice, Collaboration, WebEx, Cloud Voice, SaaS, Networks, Microsoft

Id: XkjmlVGKO_o

Length: 18min 13sec (1093 seconds)

Published: Sun Mar 28 2021