Network Engineer Phone Screen

Bl8ckr0uter wrote: »

Well I have a phone screen for a Network Engineer Job on Monday. I have been reviewing my CCNA level stuff (as this is a CCNA/CCNP job) and they are looking for someone to join their team and grow--quickly. At any rate I am trying to think of things I should not F up, any ideas good people of TE? For those of you are are in network engineering (and in hiring roles) what types of things do you look for in JRs? Anything you guys think I should ask?

I look for sound fundementals

1. OSI model
2. TCP Handshake

Now on to CCNA Stuff

1. Vlans, Trunks, Sub netting skills, Basic Campus Design
2. Basic EIGRP(Know distance vector), OSPF(know they are link state),
3. Spanning Tree Basics

If they can do very well here answering 90 percent I will look at there prior job and start to dig into how well the know the protocols if they used them at the last job

IE they were on a OSPF network

I will ask about LSA types, differnt OSPF areas,
Give me 2 ways to enable OSPF
What does "router ospf 1" do for me
what is the importance of having a loopback
Does network 10.0.0.0 255.255.2555 255 area 1. Add the 10 network into OSPF?

IF the were working a lot with switching?

When you create a new Vlan how many spanning tree instance do you get if you pulled a cisco switch out of the box?

Where would you use portfast on a switch?

How many ports can you have in a ether channel?

If you have multiple ether channel links on one switch in the same vlan would they be affect by spanning tree? If so what options do you have to get around it?

And so on. I usually go until they are broken.

Thanks for the information. I really need to work on my switching (basically haven't studied or thought about it in 14 months

For your JRs, What do you have them do during day to day work?

Bl8ckr0uter wrote: »

Thanks for the information. I really need to work on my switching (basically haven't studied or thought about it in 14 months

For your JRs, What do you have them do during day to day work?

IOS updates,

Last half mile(sometimes the demark is pretty far away from where the equipment will go and we may need to get fiber extended to the final destionation)

Rack/Stack

Small site setups (1 router, 1-2 switches)

"Add this config to a router a 12 am, call me if it breaks"

Check this config out for me tell me where I screwed up

Go to this location with a console cable and your laptop, call me when u get there.

After a few months of this guys usually have a hang of it and we start letting them do there own projects end to end without hovering over them. At this time if the management wasn't paying them right they usually move on, as the most raise the job would give them is like 10-15 percent where they can get as high as 30 with a new compay. Nature of the way things work.

Zartanasaurus

shodown wrote: »

If you have multiple ether channel links on one switch in the same vlan would they be affect by spanning tree? If so what options do you have to get around it?

I think you have me stumped here. By multiple links, I assume you mean a port-channel 1, port-channel 2, etc all in the same VLAN and connected to another switch? All the links in one port-channel are seen as one, so there is no looping issue involved and STP isn't involved if one of the links go down. Multiple port-channels connected to another switch would still cause a loop. I dunno how or why you'd want to get around that.

Zartanasaurus wrote: »

I think you have me stumped here. By multiple links, I assume you mean a port-channel 1, port-channel 2, etc all in the same VLAN and connected to another switch? All the links in one port-channel are seen as one, so there is no looping issue involved and STP isn't involved if one of the links go down. Multiple port-channels connected to another switch would still cause a loop. I dunno how or why you'd want to get around that.

I meant to add that if they are in the same reduant paths would they be affected by spanning tree

If those were all Ether channels in the same VLAN would they be affected by spanning-tree. If so what are your options around it. This is a questions I was asked before.

I'm stumped.

apr911

Here's a big one people forget and tends to be looked at by most Network Engineer positions... Know the phases of VPN, what they do, what protocols, etc.

shednik

in addition to what has been said my advice would be to be honest and not be afraid to say I haven't worked with X in awhile but if I needed to here is what I would do to get started.

I'd say also make sure you read up a little on the company and make sure you know what they do business in.

I've been applying at a few places so I've been brushing up on my interviewing skills a little.

shednik

shodown wrote: »

I meant to add that if they are in the same reduant paths would they be affected by spanning tree

If those were all Ether channels in the same VLAN would they be affected by spanning-tree. If so what are your options around it. This is a questions I was asked before.

You could say forget L2 and go for a L3 Port channel

I think the way you phrased it is what is causing Kevin to get stumped, I'm not 100% of what you're looking for either.

shednik wrote: »

You could say forget L2 and go for a L3 Port channel

I think the way you phrased it is what is causing Kevin to get stumped, I'm not 100% of what you're looking for either.

Well, he's either asking about having multiple port channels in the same vlan, or he's asking about the individual links that comprise a single port channel, and are all in the same vlan.

It's probably good to be able to answer it either way!

For the latter, then no, each individual link is not part of STP, only the actual port channel is, so as long as one link in the bundle stays up, no STP reconvergence is forced.

Of course, turning it into a routed link removes it from any STP consideration altogether, but you have to consider whether or not you have services that need layer 2 adjacency as to whether or not you can do that.

shednik

Thats what I figured he meant just the way it was worded left it for interpretation, I just added the L3 etherchannel answer to be a smart ass

Forsaken_GA wrote: »

Well, he's either asking about having multiple port channels in the same vlan, or he's asking about the individual links that comprise a single port channel, and are all in the same vlan.

It's probably good to be able to answer it either way!

For the latter, then no, each individual link is not part of STP, only the actual port channel is, so as long as one link in the bundle stays up, no STP reconvergence is forced.

Of course, turning it into a routed link removes it from any STP consideration altogether, but you have to consider whether or not you have services that need layer 2 adjacency as to whether or not you can do that.

Multiple port channels in the same vlan. Turning it into a layer 3 link is the best option if its available, which depending on the environment like you said may not be feasible. This was asked of me during a CCNP level interview, as a Voice guy I really didn't know so I just thought about the technology worked and got it right.

shodown wrote: »

Multiple port channels in the same vlan. Turning it into a layer 3 link is the best option if its available, which depending on the environment like you said may not be feasible. This was asked of me during a CCNP level interview, as a Voice guy I really didn't know so I just thought about the technology worked and got it right.

Ah. Ok now that makes sense. I guess I really need to just obsess with networking. Having the CCNP and getting CCNP level experience is different, ey?

shodown wrote: »

Multiple port channels in the same vlan. Turning it into a layer 3 link is the best option if its available, which depending on the environment like you said may not be feasible. This was asked of me during a CCNP level interview, as a Voice guy I really didn't know so I just thought about the technology worked and got it right.

Yeah, if you've got multiple port channels in the same vlan, you can most likely translate one to a routed link, and let the other one keep the layer 2 adjacency, assuming your hardware will support layer3 port channel. That way you can actually get use out of both links instead of STP blocking one

Bl8ckr0uter wrote: »

Ah. Ok now that makes sense. I guess I really need to just obsess with networking. Having the CCNP and getting CCNP level experience is different, ey?

Oh, you have no idea.... so very very much that Cisco does not teach

Forsaken_GA wrote: »

Oh, you have no idea.... so very very much that Cisco does not teach

Oh I didn't mean that as an attack on anyone. I was just looking at the objectives of the CCNA and CCNP and I just had some many questions that I don't think will be answered. The SWITCH book doesn't seem like it is going to help either.

BroadcastStorm

shodown wrote: »

IOS updates,

Last half mile(sometimes the demark is pretty far away from where the equipment will go and we may need to get fiber extended to the final destionation)

Rack/Stack

Small site setups (1 router, 1-2 switches)

"Add this config to a router a 12 am, call me if it breaks"

Check this config out for me tell me where I screwed up

Go to this location with a console cable and your laptop, call me when u get there.

After a few months of this guys usually have a hang of it and we start letting them do there own projects end to end without hovering over them. At this time if the management wasn't paying them right they usually move on, as the most raise the job would give them is like 10-15 percent where they can get as high as 30 with a new compay. Nature of the way things work.

If I was the main net engineer I would restrict ur access on TACACS+ lol so u don't get excited, and bring down the roof, goodluck bud I'm sure you will do great...

Bl8ckr0uter wrote: »

Oh I didn't mean that as an attack on anyone. I was just looking at the objectives of the CCNA and CCNP and I just had some many questions that I don't think will be answered. The SWITCH book doesn't seem like it is going to help either.

Oh, I didn't view that as an attack or anything, I'm agreeing with you! Anyone who thinks the CCNP teaches you everything you need to know is in for a very rude awakening when they get their hands on a real network

Hell, even the CCIE isn't that good. Really, the only thing the certification tracks give you is the foundation to be able to have a shot to track down and fix the problem. I think the most important part of the certification process is that you're basically teaching yourself how to learn. After that, it's up to the ingenuity of the individual engineer to get anything done.

BroadcastStorm wrote: »

If I was the main net engineer I would restrict ur access on TACACS+ lol so u don't get excited, and bring down the roof, goodluck bud I'm sure you will do great...

Oh, I don't know if I'd go that far.

I do have RANCID setup so I can tell EXACTLY what changes were made, and I have sec running on the syslog box to email me whenever someone actually does make a change, so I know who's at fault.

Forsaken_GA wrote: »

Oh, I don't know if I'd go that far.

I do have RANCID setup so I can tell EXACTLY what changes were made, and I have sec running on the syslog box to email me whenever someone actually does make a change, so I know who's at fault.

Interesting. I had to google RANCID.

BroadcastStorm

Forsaken_GA wrote: »

Oh, I don't know if I'd go that far.

I do have RANCID setup so I can tell EXACTLY what changes were made, and I have sec running on the syslog box to email me whenever someone actually does make a change, so I know who's at fault.

Those are great I'm going to be doing the same due to an outside consultant the freely loves to login randomly via vpn to study and perform misconfigured stuff...

I gave the OP an advise on a separate email np

Bl8ckr0uter wrote: »

Interesting. I had to google RANCID.

RANCID and sec are tools I consider absolutely essentially for any good network administrator, especially in an environment where multiple people can access the gear.

Having RANCID diff the configs and send out changes to everyone on the team keeps folks honest, they know that their changes *will* be noticed, especially when there's not supposed to be any changes going on.

sec is Simple Event Correlator, btw - trying to google just for it will probably drive you bananas trying to figure out what I mean. I have it sit and watch a syslog file and when predetermined patterns fire off, I get an email about it

We give full access, no since in you being scared. All network changes have to be approved anyway. Hell even if more senior engineers break something they get written up if there wasn't a change request in. This was at a older job, but there was always a NOC manager on shift who could approve changes, so it wasn't hard to get them done even at 2am as someone was awake on watch.

Having a CCNP gets you a call, being able to actually understand the technology and being able to do something with it is different. I go over the material all the time.

SteveO86

Forsaken_GA wrote: »

Oh, I didn't view that as an attack or anything, I'm agreeing with you! Anyone who thinks the CCNP teaches you everything you need to know is in for a very rude awakening when they get their hands on a real network

Amen to that one.

Forsaken_GA wrote: »

Hell, even the CCIE isn't that good. Really, the only thing the certification tracks give you is the foundation to be able to have a shot to track down and fix the problem. I think the most important part of the certification process is that you're basically teaching yourself how to learn. After that, it's up to the ingenuity of the individual engineer to get anything done.

I can't say anything regarding the CCIE but yea, you don't really run into many issues you read about in the Cisco press books. (Especially with Wireless I almost feel the CCNA Wireless is a worthless credential.. but that's a different story)

Bl8ckr0uter wrote: »

Well I have a phone screen for a Network Engineer Job on Monday. I have been reviewing my CCNA level stuff (as this is a CCNA/CCNP job) and they are looking for someone to join their team and grow--quickly. At any rate I am trying to think of things I should not F up, any ideas good people of TE? For those of you are are in network engineering (and in hiring roles) what types of things do you look for in JRs? Anything you guys think I should ask?

Good luck on the interview Monday!

I'd also try and focus on the subjects in the job description. If they wanted someone more for a WAN (Routing protocols, route maps, IPSec, Firewalls) or more so the LAN (L3 Redundancy, etherchannel, vtp/stp timers, etc), or just focus on what you can or what you consider your weak points to be. It would probably be good to mention your working toward your CCDA, especially for an engineering role. (I know that almost contradicts what I mentioned about certs but it shows a willingness and drive to learn and advance yourself)

As far as things you should ask, I'd come up with a list yourself of things that matter. What kind of shift you get, will you be on call, will you be required to work on holidays. Do you offer any type of reimbursement for certification testing/advancing your knowledge (but you may want to save that for the second interview)

Really? CCNA Wireless worthless? Interesting. I do plan to mention that I want to have my CCDA before I start the job. I think that will help some.

shodown wrote: »

We give full access, no since in you being scared. All network changes have to be approved anyway. Hell even if more senior engineers break something they get written up if there wasn't a change request in.
This was at a older job, but there was always a NOC manager on shift who could approve changes, so it wasn't hard to get them done even at 2am as someone was awake on watch.

Yeah, we have a strict change management process as well. We have some latitude when it's an emergency (we refer to that as KTLO, Keep The Lights On), but other than that, you have to submit an RFC, defend it at one of the twice weekly change management meetings, and get it approved by a quorum of senior management and staff. If you decide to go ahead and bypass that and make changes that aren't critical to keeping the business running, then your name becomes Lucy, and you got some 'splaining to do.

Forsaken_GA wrote: »

Yeah, we have a strict change management process as well. We have some latitude when it's an emergency (we refer to that as KTLO, Keep The Lights On), but other than that, you have to submit an RFC, defend it at one of the twice weekly change management meetings, and get it approved by a quorum of senior management and staff. If you decide to go ahead and bypass that and make changes that aren't critical to keeping the business running, then your name becomes Lucy, and you got some 'splaining to do.

Ours wasn't that crazy, but we had weekly meetings also with all of other IT staff, Any new routers or firewalls to the network had to be approved, but you were changing routes, adding static's and so on you just needed the small change ticket (took 10 min). It was good without being to insane. Now crazier changes like new route maps, new access-list, were looked at with a few sets of eyes. We also had the oh sh1t policy where if something was down you had some leeway to get things back up.

shodown wrote: »

Ours wasn't that crazy, but we had weekly meetings also with all of other IT staff, Any new routers or firewalls to the network had to be approved, but you were changing routes, adding static's and so on you just needed the small change ticket (took 10 min). It was good without being to insane. Now crazier changes like new route maps, new access-list, were looked at with a few sets of eyes. We also had the oh sh1t policy where if something was down you had some leeway to get things back up.

Yeah, unfortunately, we have extremely strict SLA's with our clients, so any outages which occur outside of maintenance windows that we've notified them about have a deep impact on revenue. Adjusting to the corporate workflow took some getting used to, since I could pretty much do whatever I wanted at my old job hehe

So how did you guys make your break into Network Engineering?