Linux bridge STP long path cost (802.1t-2001)

A few years ago, we had to implement STP on Linux boxes, using the long path cost standard. If changing the cost values from userspace is not really your thing, here's a patched br_if.c source (mind you, it's for an old kernel version, probably 2.6.17 or something).

Edit: for those who are interested in the actual numbers, not the Linux code:

http://en.wikipedia.org/wiki/Spanning_tree_protocol#Data_rate_and_STP_path_cost

Cisco 2500 frame relay switch - for the CCNP

Top fun for the weekend -if you don't have a life- : build a frame relay network in your Cisco home lab!

As it turns out, the Cisco 2500 series can do frame relay switching, and has more than one serial interface, so it actually makes sense to do such thing.

You can find a config here, and a discussion here.

HP AIS - Network Infrastructure [2011]

It appears that HP joined the fast-track certification solution club after Juniper and Brocade:

you can get a HP AIS certification with a valid CCNA and a web-based exam.

So while the ASE - Campus LAN cert is getting phased out, Cisco and H3C folks can get some new types of ASE and MASE certifications.

On a related note, I think the HP networking exams got quite a bit harder, with the 3Com/H3C acquisition: now you have to know both the old HP network OS, and the Comware OS, and now we have some decent routers in the portfolio, not just the good old 7000dl series.

Cisco Aironet 1231 with PowerDsine midspan POE

Lesson of the week: the Aironet 1231 series access points use a messed-up version of pre-standard POE.

We use PowerDsine 6524 midspans, which support 802.3af and and pre-standard devices just fine. They power our Cisco IP phones, the 1100 series access points (pre-standard) and our brand-new Aruba APs. But not our 1231 APs.

Here's the trick: both 1130 and 1230 series APs use reverse-polarity power, compared to the POE standard. The 1130 series contains an internal diode-bridge, which swaps the polarity, if necessary, so they work just fine. The 1200 don't. So what you need is a custom patch cord, which crosses the 4-5 and 7-8 pairs (usually the blue and brown).

It's time to Cisco

I'm proud to report that i've got a new job, as a full-time network admin. No user support, no more installing XP boxes, only the phat tubes. Yeah.

And it's a university, so we've got plenty of chicks...

It's a Cisco place, with some HP boxes, so i won't play with Juniper gear for a while, apart my own Netscreen at home. Oh well...

An interesting upcoming project is with an Aruba Mobility Controller, a centrally managed WiFi solution. Brochures say it's cool, user guide says it's cool, maybe it'll be cool. Stay tuned for details as we progress.
On a related note, Juniper just put up it's new Wireless fundamentals e-learning course.

What we learned today: if you're upgrading a Cisco MARS appliance from 4.2.2 to 4.2.3, read the release notes first, and check out the MARS blog.

To gain root access to the box: reboot, hold right Shift key during POST and Lilo, when Lilo prompt appears, press any key, like 'A'. Boot with 'linux init=/bin/bash', remount the root fs in rw mode, and passwd with a smile. Reboot, after pnadmin login, use the 'expert' command.

After that, you can clean up the /u01 partition, so the failed 4.2.3 upgrade can start again...