Arista Networks CFO Kelyn Brannon is stepping down, and the person taking her place for now is going to be Andreas Bechtolsheim.

You know, Andy Bechtolsheim: chairman and chief development officer; a founder of Arista and also of Sun Microsystems; super-technologist worth something like $4 billion. And apparently an accounting whiz, at least for now (and just in time for tax season).

It doesn't necessarily mean anything. But it sure makes for an amusing headline — one better saved for April 2 rather than April 1, the day of the announcement.

Bechtolsheim actually has CFO experience on his resume, albeit with Arista — he held the post in the company's early days. Of course, Bechtolsheim is better known for doing Ph.D. work at Stanford University, where he devised the terminal that became the Sun workstation.

Brannon is leaving for personal reasons, according to Arista's announcement, made yesterday after the markets closed. ("Personal reasons" sometimes means another job, although Arista's high profile makes that seem less likely here.) Brannon left a previous CFO position, with Calix, "with similar suddenness," writes analyst Simon Leopold of Raymond James, who put out a note on Arista this morning.

While nothing appears to be wrong, any C-level departure has to be considered a "yellow flag" against a company, Leopold writes. "We have no fundamental basis to adjust our estimates or views on Arista's business, but such management transitions tend to create worry."

Of course, Bechtolsheim is just an interim CFO. The search for Brannon's permanent replacement is underway, Arista says.

Arista announced Brannon's departure yesterday after the markets closed. Arista shares were down $3.28 (4.7%) at $66.34 this morning.

(Photo via Wikipedia.)