Who writes this site
I am Alex Xu, a senior network architect based in Shanghai. I have worked on carrier and enterprise networks since 2003 — IP/MPLS backbones, data-centre fabrics, AI-cluster networking, SD-WAN and the automation around all of it.
What this site is
One person's working notes. The homepage is my professional profile; Notes is where I write down things I have had to work out the hard way — how a routing protocol actually behaves when a link flaps at 3 a.m., why a fabric that looks fully redundant still has a shared failure domain, what breaks in a migration that the design document did not mention.
I write about what I have operated or designed. If I have only read about something, I say so, or I do not write the piece.
How it is produced
Notes are written by me between projects. Drafts are sometimes prepared with the help of a language model for structure and editing; every technical claim, configuration excerpt and figure is checked by me against a device, a lab or a document I actually hold before it is published. Configuration examples are illustrative and vendor-neutral unless the piece says otherwise — check them against your own release before you paste them.
There is no content team, no ghostwriter and no publishing schedule bought from anyone.
Corrections
If something here is wrong, email alex.xu@ccie13192.com with the URL and the specific claim. Technical corrections are applied to the article with a note stating what changed. I will not quietly rewrite a piece to hide an error.
How the site is funded
The site carries Google AdSense advertising. Advertisers do not see or influence the content, and no vendor pays for coverage, ranking or a mention. There are no affiliate links in the notes.
What is collected when you read a page — and how to opt out of personalised advertising — is described in the privacy policy.
Contact
Email alex.xu@ccie13192.com. I reply to messages within a business day, and to correction requests within three business days. Details on the contact page.