IOS: Reverse SSH Console Access

I recently needed to secure the reverse console access using Cisco IOS router. Now for many years, we have been doing this over telnet and the configuration has been straightforward. But configuring it to support SSH instead of telnet is a little bit different, awkward in fact. Read more

Monolingual, OSX and 10.5.3 Update - Saving Space

I use Monolingual to save space on the MAC OSX. Quick word on how much space you can save and how to do it. Read more

Network Dictionary - TLA and eTLA

TLA is a recursive acronym for Three Letter Acronym.

Which is pretty funny.

eTLA - eXtended Three Letter Acronym - used to describe four letter acronym.

Which is even funnier.

Note the use of best marketing practice with dropped ‘e’. Very kewl

Who said nerds don’t have any humour.

Article: The Future of Storage - Seven Fundamental Reasons Why FCoE Will Fail

An article I wrote on concerns about FCoE adoption has been posted at The Future of Storage and reviews seven reasons why FCoE might not achieve critical mass in the marketplace.

Feedback appreciated. Is anyone considering using FCoE in real life ?

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iSCSI Network Designs: Part 5 - iSCSI Multipathing, Host Bus Adapters, High Availability and Redundancy

In iSCSI Part 3 - Server Side - iSCSI Host Bus Adapters and IP Performance I looked at how server side issues would affect the traffic generated on a per server basis. I recommended that you use iSCSI HBAs for high intensity servers to meet the high levels of performance.

The next level is evaluate how the server should connect to the network, specifically, this means how many ethernet ports you need, and what configuration is needed to support them to deliver high availability / redundancy and increased bandwidth.

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Aid to Seven Layer ISO Model

Over the years I have memorized the IOS seven layer model. But sometimes I need to double think myself to check and I found this on Wikipedia
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Network Dictionary - ASAi

ASAi - (ass-i) - The correct plural term for more than one Cisco ASA firewall appliances. Read more

Don’t Tell Me iSCSI Is Complicated if Fibrechannel Looks Like This

I am working my way through the next couple of articles on iSCSI Network Design. Its getting complicated is some ways. I noticed this article todayhttp://vinf.net/2008/04/09/how-does-an-hp-fibre-channel-virtual-connect-module-work/ explaining how Fibrechannel failover work for a HP Fibrechannel Virtual Connect in a blade server chassis. It is all rather confusing, and seemingly no more complex that the iSCSI network design.

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iSCSI Network Designs: Part 4 - Fibrechannel Integration

Its possible that you would already have some Fibrechannel in your estate. Perhaps the cost of Fibrechannel for some new servers is too much when you calculate the HBA and Fibrechannel switch port costs, or you don’t need the complexity of Fibrechannel for a simple server setup. Lets look at options for connecting to the Fibrechannel nteworks.
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Nerdgasm: Cisco ACE Web Application Firewall Announced

Cisco announces the Web Application Features for the ACE module

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Determine Which SFP Is Installed in Your Cisco Line Module

I needed to work out whether a SFP was installed into a C6500 line card today. (OK, so I don’t do this kind of thing very often) and it took me a few minutes to realise where I would get this information.
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Network Dictionary - Pixen

pixen - (picks-sen)

The correct term for a group of PIX firewalls. I have decided that the correct term is Pixen after banging my head on the desk for much of the day.

PIXen - derived from the term Vaxen The plural canonically used among hackers for the DEC VAX computers

Terms deprecated as a result of this advisory -

pixes	just looks naff
pixies	not usable in a corporate settings
pix	The plural noun form just doesn’t work. For example: sheep is one sheep two sheep etc. Problem is the people don’t understand or comprehend that term in a sentence full of other jargon.

Consider: So if we drop the ASA into VLAN for the VPN head end at the top of DC SONA chain, migrate the ACL and config ready for the flip.

iSCSI Network Designs: Part 3 - Server Side - iSCSI Host Bus Adapters and IP Performance

I have been researching iSCSI impementations on the server to try and understand the dfference between them and to come to grips with how they work. This article looks to compare the various methods of connecting to a iSCSI network.

It seems that many people do not know or understand that the generation and transmission of IP packets is CPU intensive process. In some operating systems, it can also be very latent since there are many transfers across the memory bus and the PCI bus before the data is actually transmitted.

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Network Dictionary - iSCSI

iSCSI - (eye-scuzzee)

- a protocol designed to transport SCSI block data across an IP network thus allowing a single network infrastructure.

- a protocol used by networking teams so they don’t have to understand storage (thanks to Jeff Darcy at Pl.atyp.us)

compare with Fibrechannel

Network Dictionary- Human Remorse

Human Remorse

Descriptive name for Human Resource department of any company. Remorse means a sense of guilt or distress for past wrongs, and that pretty much how you feel after dealing with them. Having to deal with Human Resources just feels wrong.

Data Networks - More Reliable to Than Storage Networks ?

I was participating in a storage design discussion and a Storage person threw up their most common complaint about networking - “we don’t know how to build reliable networks”. Let me take a shot at that. Read more