Eric Stewart: Running Off At The Mouth

Optical Networking: Basics, DWDM, ROADM

by on Oct.26, 2015, under Internet Service Providers, Networking, Technology

$JOB is getting into some new and interesting stuff; stuff that, if you’re not an Internet Service Provider, could be a bit of a black box to you; you might be used to your ISP saying “Here’s a cable, your equipment is on the other end”. Here’s what we’ve been working on and what I’ve been able to make of it so far.

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Cat 6500 to Nexus 7K Migration Note: Or, The 6500’s Dirty Little Secret

by on Aug.13, 2015, under Networking, Technology

In which I regale you with a tale involving the salacious behavior of the Catalyst 6500 when compared to the more chaste Nexus 7K line.

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NTP, ntpd, ntpq, and The Perils Of “Time”

by on Aug.06, 2015, under Computers, Networking, Technology

We ran into a “time” situation at work, and I learned quite a bit about how NTPD works, and what exactly all the information in ntpq means. This has to do with the “Leap Second” that was instituted on June 30, 2015.

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Lessons in Troubleshooting: IPv6, OSPF, and Strange Packet Loss

by on Jul.24, 2015, under Networking, Technology

Attempting (in my scatterbrained manner) to cover all the bases of an interesting issue I encountered recently and failed to fix without assistance. It illustrates why I’m not a CCIE yet, and why, no matter what you see, you shouldn’t assume anything when working through odd issues.

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Nexus 7700 Part VII: TCAM Woes and Solutions, Part 2

by on Jul.24, 2015, under Networking, Technology

A revisit to an earlier post and why what I outlined there was a bad idea. Using Bank Chaining, while allowing you to use more banks for ACLs, has its penalties …

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Eureka Moment: auto-summary on RIPv2 – What It Does

by on Jun.30, 2015, under Networking, Technology

Two things covered in this post: what I learned about how “auto-summary” on RIPv2 works, and also some particulars about RIPv2 (and possibly other routing protocols) and how it advertises routes to neighbors.

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Cisco Live 2015

by on Jun.12, 2015, under Networking, Technology

Cisco Live 2015. Yeah, there are things I can say about it that are negative. But even with all that, it was, for me, the best so far. Here’s my review and a few pictures …

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CCIE Studies: IS-IS Lab Notes

by on Mar.22, 2015, under Networking, Technology

Just a couple of notes for myself that Google didn’t make as clear as it should have for me.

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CCIE Studies: OSPF E1 vs E2 For Dummies

by on Mar.14, 2015, under Networking, Technology

Restating what I’ve pulled from other sources, and clarifying that there actually is a difference. It’s commonly said that “E2 routes will not include path cost,” but that’s an oversimplification of the difference and a somewhat misleading statement, because, in some cases, path cost is considered. Here’s the scoop.

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Nexus 7700 Part VI: vPC Part II: You Can’t Use The Peer-Link For Everything

by on Feb.21, 2015, under Networking, Technology

$JOB doesn’t have as much of a testing environment as one might like to have, so sometimes you discover issues during implementation that, once you resolve them, you can’t go back and pick apart. An issue with the vPC Peer link appears to have prevented one of our 7710’s going into our data center from properly forming an OSPF adjacency with the DR.

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