February 2009 - Test - lists.nanog.org

Network topology
by Colin Alston 15 Nov '13

15 Nov '13

Hi all I'm considering trying to come up with some means to automatically detect a networks topology and draw pretty pictures. This is somewhat boring though if a network isn't well arranged with VLANs and q-tag trunk routers and so on (It will just look like a big cloud of junk connected off an assumed switch). Is there any kind of cunning trick to detect standard layer2 switches along a path without stuff like STP?

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Inventory and workflow management systems
by vijay gill 26 May '13

26 May '13

What software solution do people use for inventory management for things like riser/conduit drawdown, fiber inventory, physical topology store, CLR/DLR, x-connect, contracts, port inventory, etc. Any experiences in integrating workflow into those packages for work orders, modeling, drawdown levels, etc. /vijay

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Re: Re: What is the most standard subnet length on internet
by 정치영 03 Aug '09

03 Aug '09

Suresh, Yes, I guess my concern is close to the second meaning. It seems so simple. Currently annoucement of /24 seems to be okey, most upstream providers accept this. However I wonder if there is any ground rule based on any standard or official recommandation. If there is some standardized rule about prefix length to be annouced, I will make my bgp & IP allocation policy of each data center of my company, and I will be able to more fairly and squarely speak to my customer like this "You have to change your server's IP address if you want move your server to other place" chiyoung ============================================= Chi-Young Joung SAMSUNG NETWORKS Inc. Email: lionair(a)samsung.com Tel +82 70 7015 0623, Mobile +82 17 520 9193 Fax +82 70 7016 0031 ============================================= ------- Original Message ------- Sender : Suresh Ramasubramanian<ops.lists(a)gmail.com> Date : 2008-12-19 12:37 (GMT+09:00) Title : Re: What is the most standard subnet length on internet Chi Young, let me clarify one thing here .. Do you mean IP allocation as in subnet allocation, swipping in apnic or through a rwhois server etc? Or do you mean "what is the minimum subnet size I can announce on the internet and have other providers not drop it on the floor"? srs On Fri, Dec 19, 2008 at 8:10 AM, 정치영 <lionair(a)samsung.com> wrote: > Hi everyone, > > I'm going to rebuild IP allocation policy of my company and I am looking for some standard reference for my policy. > I have already studied some standard like RFC1518, RIPE181, RFC2050 and I got it is very important to maintain hierachy structure. > However, what I am really wondering is what is the most standard subnet length that always can be guaranteed through Internet. less than /24 bit ? > I could not find any documents about that, which subnet length is most proper value and pursue internet standard policy ? >

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Re: Re: What is the most standard subnet length on internet
by 정치영 26 Jul '09

26 Jul '09

Hi all, I appreciate many people gave me advices, Some of persons asked me about my questions, I'm sorry for that I couldn't reply to everyone. Because of your help, I could get many opinions and standards regarding IP allocation policy. by the way, in APNIC's IP allocation sizes policy, there is a comments like below. "Below are the minimum sizes for allocations and assignments, This information is provided at the request of the ISP community to assist in filtering policy decisions " Currently, is there any provider filtering routes under LIR's minimum allocation size such as /22 ? Best regards, ============================================= Chi-Young Joung SAMSUNG NETWORKS Inc. Email: lionair(a)samsung.com Tel +82 70 7015 0623, Mobile +82 17 520 9193 Fax +82 70 7016 0031 ============================================= ------- Original Message ------- Sender : Danny McPherson<danny(a)tcb.net> Date : 2008-12-21 02:42 (GMT+09:00) Title : Re: What is the most standard subnet length on internet On Dec 18, 2008, at 9:43 PM, 정치영 wrote: > Suresh, > > Yes, I guess my concern is close to the second meaning. > > It seems so simple. Currently annoucement of /24 seems to be okey, > most upstream providers accept this. > However I wonder if there is any ground rule based on any standard > or official recommandation. > If there is some standardized rule about prefix length to be > annouced, I will make my bgp & IP allocation policy of > each data center of my company, and I will be able to more fairly > and squarely speak to my customer like this > "You have to change your server's IP address if you want move your > server to other place" Some useful guidance is provided here (and in subsequent references) as well: An Architecture for IP Address Allocation with CIDR <http://tools.ietf.org/html/rfc1518> Classless Inter-Domain Routing (CIDR): an Address Assignment and Aggregation Strategy <http://tools.ietf.org/html/rfc1519> Network Renumbering Overview <http://tools.ietf.org/html/rfc2071> A Framework for Inter-Domain Route Aggregation <http://tools.ietf.org/html/rfc2519> HTH, -danny

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Network SLA
by Saqib Ilyas 15 Apr '09

15 Apr '09

Greetings I am curious to know about any tools/techniques that a service provider uses to assess an SLA before signing it. That is to say, how does an administrator know if he/she can meet what he is promising. Is it based on experience? Are there commonly used tools for this? Thanks and best regards -- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences

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Re: Yahoo and their mail filters..
by Suresh Ramasubramanian 25 Mar '09

25 Mar '09

On Wed, Feb 25, 2009 at 5:02 PM, Niall Donegan <niall(a)blacknight.com> wrote: > > Another interesting side effect of that is email forwarder accounts. > Take a user who gets a domain on our shared hosting setup and forwards > the email for certain users to a Yahoo account. If those mails are > marked as spam, it seems to be our server that gets blacklisted rather > than the originating server. > No surprise. Guess whose IP is the one handing off to yahoo? If you have forwarding users - * Spam filter them to reject spam rather than simply tag and forward it. * Isolate your forwarding traffic through a single IP, Let ISPs know. > Feedback loops often aren't that useful either. We're on the AOL Scomp > feedback loop, and we've often got fairly personal email sent to our > abuse desk because the users simply press spam rather than delete. You have a far smaller userbase, and a userbase you know. For us, with random nigerians and other spammers signing up / trying to sign up all the time, FBLs are invaluable as a realtime notification of spam issues. And as I said random misdirected spam reports wont trigger a block as much as your leaking forwarded spam. Or your getting a hacked cgi/php or a spammer installed direct to mx spamware. [so if you are cpanel - smtp tweak/csf firewall and mod_security for apache should be default on your install if you havent already done so] -srs

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real hardware router VS linux router
by Deric Kwok 18 Mar '09

18 Mar '09

Hi All Actually, what is the different hardware router VS linux router? Have you had experience to compare real router eg: cisco VS linux router? eg: streaming speed... tcp / udp Thank you for your information

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Leap second tonight
by Kevin Day 18 Mar '09

18 Mar '09

Just a reminder that there's a leap second tonight. Last time I watched for what happened on 01/01/2006, there was a little bit of chaos: http://markmail.org/message/cpoj3jw5onzhhjkr?q=%22kevin+day%22+leap+second+… I've been told that some of the causes of these problems are fixed on any reasonably recent ntp distribution, but just in case, you might wanna keep an eye out if you're seeing any weirdness. The worst damage I'd heard from anyone after that event was their clock being significantly off for several hours. -- Kevin

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MAC address confusion
by Saku Ytti 04 Mar '09

04 Mar '09

Whic one of these, is locally assigned unicast MAC address, when talking about output format CSCO uses? 4000.0000.0000 (Local IXPs choice) 0200.0000.0000 (My money is here) http://standards.ieee.org/regauth/oui/oui.txt 02-07-01 (hex) RACAL-DATACOM A0-6A-00 (hex) Verilink Corporation In either case two of the lowest or highest bits of 1st octet seems to be happily used to assign addresses. What am I missing here? -- ++ytti

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23456 without AS4_PATH?
by Saku Ytti 02 Mar '09

02 Mar '09

Anyone else seeing this: *> 91.196.186.0/24 62.237.167.25 0 3292 3549 15703 43531 23456 i http://www.ietf.org/rfc/rfc4893.txt 6. Transition An OLD BGP speaker MUST NOT use AS_TRANS as its Autonomous System number. -- ++ytti

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