(ABC News)

Robert Gates's new memoir is making waves in Washington but it certainly hasn't dampened his popularity at the Pentagon.

Well over a thousand people showed up at the Pentagon food court today to have the former Defense Secretary personally sign a copy of his new book "Duty."

Vendors sold out the 900 copies they had brought for the signing, but there were many others on line who had brought previously purchased copies for him to sign. And many others were turned away after the line was capped an hour into the two-hour signing.

The line of civilian and military employees wound its way across a large stretch of the food court and eventually headed out into the Pentagon Courtyard. The cold weather did not deter others from patiently waiting outside, even as the line moved briskly for the brief chance of having Gates sign their books.

Gates received applause as he entered the food court area and headed to the table where he methodically autographed every copy of his book presented to him. Most people received a simple "Robert Gates" on the book's title page, but some of his old personal staff, who had waited on line, received more detailed messages.

Robert Gates has begun signing copies of his book for the hundreds of Pentagon employees who've shown up today. pic.twitter.com/hHv6agIOXY

- luis martinez (@LMartinezABC) January 16, 2014

Prior to heading to the book signing, Gates had a private meeting with Defense Secretary Chuck Hagel.

"It was a great conversation," Pentagon Press Secretary Rear Admiral John Kirby told reporters at a press briefing.

In light of the fact that Gates's book has created a stir in Washington and prompted rebuttals from the White House, Kirby was asked if Hagel had an opinion on the book.

"He's not going to take a position on the opinions that are expressed in the book or make a statement about whether the book should have been written or not," said Kirby. He restated that last week, during a tour of an Air Force base in New Mexico, Hagel had said he was not going to second-guess the motivations of others.

Asked if Gates's presence in the building reflected the Pentagon's endorsement of the book, Kirby chuckled and said: "The fact that he's signing the book in the Pentagon isn't, doesn't connote endorsement of the content of the book."

He added that "we all have great respect and admiration for Secretary Gates. … All of us have great regard for him and his leadership here, and we're glad to welcome him here into the Pentagon to sign copies of it for the folks that work here."

Book signings at the Pentagon are approved by the Washington Headquarters Service, which is the administrative office for Defense Department facilities in the Washington, D.C., area. Former Defense Secretary Donald Rumsfeld has also drawn big crowds at past book signings.

Gates did not take questions from the press who showed up to cover the book signing, though he did take a quick question from someone in line who asked Gates if he had become a Seattle Seahawks fan.

"Absolutely," said Gates, who retired to Washington state after he finished his tour as Defense Secretary.