Sergeant Major Eirich graduated from Company “A”, First Recruit Training Battalion on April 11, 2003 at Marine Corps Recruit Depot Parris Island, SC with follow on orders to Marine Combat Training at Marine Corps Base Camp Lejeune, NC, and graduated May 13, 2003.
He proceeded to military occupational specialty school at Logistics Operations School aboard Camp Johnson, NC, for completion of the Automotive Maintenance Technician Basic Course. Sergeant Major Eirich then received orders and reported to 2d Maintenance Battalion, Camp Lejeune, NC, on September 24, 2003.
While assigned to 2d Maintenance Battalion, Sergeant Major Eirich earned the rank of Lance Corporal and served as an Intermediate Automotive Technician. In 2004, Sergeant Major Eirich deployed in support of 1st Marine Headquarters Group to Camp Fallujah, Iraq from September 2004 to February 2005. While deployed, Sergeant Major Eirich was promoted to Corporal. Upon return from Iraq, Sergeant Major Eirich returned to 2d Maintenance Battalion where he was promoted to the rank of Sergeant and again deployed to Al Taqaddum, Iraq in support of Operation Inherent Resolve from March 2007 to September 2007. Sergeant Major Eirich served as the Platoon Sergeant and Quality Control Chief. In April 2008, Sergeant Major Eirich received orders to Inspector Instructor Unit, 4th Landing Support Battalion (LSB), Stone Bay, NC.
While at 4th LSB, Sergeant Major Eirich served as the Maintenance Chief, Colors Sergeant, Martial Arts Instructor, and Electronic Key Management System Manager. In February 2010, Sergeant Major Eirich was promoted to Staff Sergeant and deployed to Morocco, Africa in support of African Lion 2010. In August 2011, Sergeant Major Eirich was assigned orders to Combat Logistics Battalion (CLB) 2 for duty as the Maintenance Chief.
While with CLB-2, he deployed to Afghanistan in support of Operation Freedom Sentinel from July 2012 to January 2013. Sergeant Major Eirich also served as the Maintenance Management Chief/Officer and a Martial Arts Instructor Trainer while with CLB-2 and then received orders on April 30, 2014 for duty as a formal school instructor at Logistics Operations School aboard Camp Johnson. In October 2015, he was promoted to the rank of Gunnery Sergeant and assigned the position of Team Leader for Annex 3.
On December 2, 2016, Sergeant Major Eirich was assigned orders to 3d Marine Raider Battalion. His responsibilities included assignment as the Headquarters Company First Sergeant and Staff Non-Commissioned Officer-in-Charge of the Motor Transportation section. On April 16, 2019 he was frocked to the rank of First Sergeant and assigned orders to Fleet Readiness Center East, Marine Corps Air Station Cherry Point, NC, to serve as the Senior Enlisted Advisor.
While at Fleet Readiness Center East, Sergeant Major Eirich was responsible for over 30 Marines and a detachment of over 100 Sailors. Additionally, Sergeant Major Eirich served on the Command Deck with oversight of 4000 civilian government employees and the production and maintenance of six type model series aircraft in Marine Corps Aviation. On May 26, 2021, Sergeant Major Eirich reported to 1st Combat Engineer Battalion where he served as the Bravo Company First Sergeant and Headquarters and Service Company First Sergeant. In December 2023, Sergeant Major Eirich was frocked and reported to Marine Corps Recruiting Station Chicago, for duty.
Sergeant Major Eirich holds an Associates Degree in General Studies from American Military University and a Bachelor's of Health Science from American Military University. He is the recipient of the 2021 Navy and Marine Corps Leadership award. Sergeant Major Eirich was also the recipient of the 2015 Logistics Operations School Instructor of the Year award. Additionally, he was the Honor Graduate for Motor Transport Non-Commissioned Officer School.
Sergeant Major Eirich's personal decorations include the Navy and Marine Corps Commendation Medal with three gold stars in lieu of fourth award and the Navy and Marine Corps Achievement Medal with one gold star in lieu of second award.