Arista EOS ASU and ASU2

ASU = Accelerated Software Upgrade

• EOS Docu
• 就是在Control Plane booting的时候，Hardware继续Fwd Traffic based on old state
• 等Control Plane is up and running, refresh hw. 所以Traffic disruption大概是30 seconds. 
• CLI: reload fast-boot
• 还有一个ASU+

ASU2

• 没有Document ?
• 就是加上Protocol GR，例如BGP, OSPF
• Traffic disruption is about 50ms
• CLI: reload hitless