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Re: This may be stupid but..
by Michael.Dillon＠radianz.com 11 Nov '03

11 Nov '03

>> When I interview, I start out by asking one or two key questions that >> help me quickly get to the truth. For instance at one company, when I >> has hiring NOC folks, I started by asking them to explain traceroute >> to me. >"Which one? ICMP, UDP or TCP traceroute (to name the usual ones)?" >PS: this is the answer I'd expect from applicants... but this depends >on what cluelevel you want/need in your NOC. :-) It's not the answer I would expect. First of all, the question asked the candidate to "explain" and the answer was not an explanation. In fact, the answer was just the kind of meaningless memory work that CCxx and MSxx certified people are good at. As an interviewer, I don't want short answers like you find in a multiple choice exam. I want some detail that shows that the candidate really does have some understanding of how network protocols work on the inside. Mistakes are OK because I'm not marking the person on their perfection but I'm trying to find out how they think and how they might approach network problems on the job. It's the same reason that I like to ask candidates to tell a story about some past event and how they, personally, dealt with it. If a candidate has had real personal experience of something then they will be able to tell me a story filled with detail. On the other hand, you sometimes get people who can only say "we" did this and "we" did that which leads you to believe that maybe the person was the NOC janitor or something. The best job interview questions are the ones that don't have a right answer. --Michael Dillon

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Re: Router with 2 (or more) interfaces in same network
by sthaug＠nethelp.no 11 Nov '03

11 Nov '03

> You _used_ to be able to do this (oh, over two years ago?). The address > was assigned to the interface, and the error from trying to add a duplicate > route was simply ignored, no route got added anywhere. You can figure out > when the change was made by examining the code or by seeing when the > maillists started to get flooded by people who could no longer do, > > # ifconfig if0 inet 10.0.0.1 > # ifconfig if0 alias 10.0.0.2 > > When they meant, > > # ifconfig if0 inet 10.0.0.1 > # ifconfig if0 alias 10.0.0.2 netmask 0xffffffff There is a difference, of course - Cisco is perfectly happy to let you do int fa0 ip addr 10.0.0.1 255.255.255.0 ip addr 10.0.0.2 255.255.255.0 secondary I never could understand why this should be impossible in FreeBSD. But I guess this discussion is no longer NANOG relevant :-) Steinar Haug, Nethelp consulting, sthaug(a)nethelp.no

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US LEC?
by Dave Temkin 11 Nov '03

11 Nov '03

Does anyone have any experience in dealing with US Lec? I'm working with a FastNet customer who's been sold to them in FSST's bankruptcy. We have other connectivity in the meantime. Thx, -Dave

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RE: Router with 2 (or more) interfaces in same network
by Michel Py 11 Nov '03

11 Nov '03

>> I am curious to know if its possible to have a router with its >> two interfaces, say configured as, 1.1.1.1/16 and 1.1.1.2/16. >> Theoretically, i see nothing which can stop a router from doing this. > Cisco's don't let you do this. I have always considered that > broken, although I'm sure Cisco thinks it's a feature. bridge irb inte f5/0 no ip add bridge group 1 inte f5/1 no ip add bridge group 1 inte bvi 1 ip add 1.1.1.1 255.255.0.0 bridge 1 prot ieee bridge 1 route ip bridge 1 bridge ip

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RE: Router with 2 (or more) interfaces in same network
by Truman, Michelle, RTSLS 11 Nov '03

11 Nov '03

Well you can do it if you are bridging... Michelle Truman CCIE # 8098 Principal Technical Consultant AT&T Solutions Center 651-998-0949 mtruman(a)att.com -----Original Message----- From: Leo Bicknell [mailto:bicknell@ufp.org] Sent: Tuesday, November 11, 2003 8:56 AM To: nanog(a)trapdoor.merit.edu Subject: Re: Router with 2 (or more) interfaces in same network In a message written on Tue, Nov 11, 2003 at 08:35:34AM +0000, Sugar, Sylvia wrote: > I am curious to know if its possible to have a router with its two interfaces, say configured as, > 1.1.1.1/16 and 1.1.1.2/16. Theoretically, i see nothing which can stop a router from doing this. Cisco's don't let you do this. I have always considered that broken, although I'm sure Cisco thinks it's a feature. Other routers (of note FreeBSD boxes) do this just fine. In almost all cases I've seen it done it was for more bandwidth to the box (typically inbound only, because there are no good tools on Unix boxes to split the traffic between the outgoing interfaces). I've seen it done a lot in labs where you have something like this: client 1 | | client 5 client 2 +----B----+ client 6 client 3 | | client 7 client 4 | | client 8 | | file-server-router-box | Internet Where all the clients are in one subnet, there are two interfaces, and the networks are separated (today the left and right groups on two different switches, I drew the old school picture of thinwire with a bridge in the middle. While this will work (with some boxes, again Cisco's won't let you configure the same subnet on two interfaces), it is at best a hack that helps in some specific instances. It is quite clearly not good network design. Maybe they have one of those specific instances but I'd get a lot more detail and be sure before you offer up this hack as otherwise you've got a messy config that didn't do what the customer wanted anyway. -- Leo Bicknell - bicknell(a)ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/ Read TMBG List - tmbg-list-request(a)tmbg.org, www.tmbg.org

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RE: Router with 2 (or more) interfaces in same network
by Lucas Iglesias 11 Nov '03

11 Nov '03

If you bridge, you are actually not doing routing =) You can configure a channel group with FE, but anyway it would be concider by the router as if you have only 1 interface. Regards. -----Mensaje original----- De: Frank Louwers [mailto:frank@openminds.be] Enviado el: Martes, 11 de Noviembre de 2003 11:22 a.m. Para: Lucas Iglesias CC: 'Sugar, Sylvia'; nanog(a)trapdoor.merit.edu Asunto: Re: Router with 2 (or more) interfaces in same network On Tue, Nov 11, 2003 at 11:19:21AM -0300, Lucas Iglesias wrote: > > As I know, according to the routing theory, it has no sense to have 2 > interfaces on the same net. what if you bridge on one interface, but want to have a second "backup" interface in case your config/router fscks up with the bridge? Vriendelijke groeten, Frank Louwers -- Openminds bvba www.openminds.be Tweebruggenstraat 16 - 9000 Gent - Belgium

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RE: Router with 2 (or more) interfaces in same network
by Lucas Iglesias 11 Nov '03

11 Nov '03

As I know, according to the routing theory, it has no sense to have 2 interfaces on the same net. At least, on Cisco routers is not allowed. kind regards. -----Mensaje original----- De: Sugar, Sylvia [mailto:truesylvia@yahoo.co.uk] Enviado el: Martes, 11 de Noviembre de 2003 05:36 a.m. Para: nanog(a)trapdoor.merit.edu Asunto: Router with 2 (or more) interfaces in same network Hi, I am curious to know if its possible to have a router with its two interfaces, say configured as, 1.1.1.1/16 and 1.1.1.2/16. Theoretically, i see nothing which can stop a router from doing this. But practically, is it of any use? And if used, then, when and why will somebody want to use such a kind of configuration? Would appreciate if somebody could enlighten me on this. Regards, Rasputin P.S. I have a customer who insists he wants to do this, without providing any explanations! ________________________________________________________________________ Want to chat instantly with your online friends? Get the FREE Yahoo! Messenger http://mail.messenger.yahoo.co.uk

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RE: Router with 2 (or more) interfaces in same network
by Shawn Solomon 11 Nov '03

11 Nov '03

I would guess that they actually want 1 of the following: Redundancy of some sort. Increased bandwidth to the router. -- Shawn Solomon Senior Network Engineer / Systems Design IHETS / ITN 317.263.8875 ssolomon(a)ind.net fx317.263.8831 -----Original Message----- From: Sugar, Sylvia [mailto:truesylvia@yahoo.co.uk] Sent: Tuesday, November 11, 2003 3:36 AM To: nanog(a)trapdoor.merit.edu Subject: Router with 2 (or more) interfaces in same network Hi, I am curious to know if its possible to have a router with its two interfaces, say configured as, 1.1.1.1/16 and 1.1.1.2/16. Theoretically, i see nothing which can stop a router from doing this. But practically, is it of any use? And if used, then, when and why will somebody want to use such a kind of configuration? Would appreciate if somebody could enlighten me on this. Regards, Rasputin P.S. I have a customer who insists he wants to do this, without providing any explanations! ________________________________________________________________________ Want to chat instantly with your online friends? Get the FREE Yahoo! Messenger http://mail.messenger.yahoo.co.uk

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law enforcement contacts
by Alex Yuriev 11 Nov '03

11 Nov '03

Hi, Anyone has any good law enforcement contacts that have enough clue ( or could be educated in process ) to work on catching and nailing DOS originators? Please drop me email off the list. Alex

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Re: [Re: This may be stupid but.. ]
by joshua sahala 11 Nov '03

11 Nov '03

"Peter Galbavy" <peter.galbavy(a)knowtion.net> wrote: > > A willingness, nay - a NEED, to learn and be open to new concepts is > what forward moving technology sectors (like ours I hope) need. definately - however, i know of some very smart people, with a huge drive to learn, were relegated to clueless tasks because they didn't have many many years of experience. there is a distrubing trend amongst managers/etc where they think that if you haven't already done the job for several years, you can't learn to do it, or don't have the skill to do it. i am not saying that this is universal (as demonstrated by several posts here to that effect), but i think that these are exceptions > Acronyms mean sh*t. When involved in any hiring process, I actively > avoid CCIE/MSCE/etc. laden resumes. Mentioning once, fine. Using them > like religious phrases is an indictation of, well, stupidity. certifications are often necessary to open the door - granted if you were architecting internetworks when many of today's certified 'engineers' were still in grade school, then no, certifications are probably not needed. experience is a catch-22, you need experience to get a job, but you need a job to get experience. i am not saying that certifications are a panacea, but lacking the ability to say that i built $major_isp, my certs have helped me (a little) in getting past the recruiter/hr to where my technical skills can be demonstrated > > i'm recruiter-proof. i'm not sure i'd want anyone who wasn't. > > Aye. I have *never* used my CV/Resume in getting a job. I still have > one, but it's very out of date. never is a long time perhaps it is just the fact that i am 'new' to the field, but my resume has gotten me all but one job, and my resume indirectly got me that one. my slightly bitter $0.02 /joshua > Peter > > "Walk with me through the Universe, And along the way see how all of us are Connected. Feast the eyes of your Soul, On the Love that abounds. In all places at once, seemingly endless, Like your own existence." - Stephen Hawking -

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