Brocade has a good customer base and a strong position in storage, Kerravala said, but "the question is, how do you get the Ethernet business moving? That requires a skill set that's a little bit outside of what Klayko had."

Kerravala also noted that has been volatile in recent years and has suffered declines during his tenure.

Nevertheless, Brocade didn't have a bad last quarter. Revenue for the three months ended July 28 was $555.3 million, up 10 percent from a year earlier, the company Thursday. Earnings per share of $0.09 was up from break-even in the same quarter last year.

Klayko will stay on as CEO until the company finds a replacement, Brocade said. One potential candidate is Vice President and Chief Marketing Officer John McHugh. "He's the guy who took HP's ProCurve business from no share to double-digit share" before joining Brocade, Kerravala said.

But he thinks it more likely the new CEO will come from outside the company.