Updating Your Cisco Catalyst 3560: A Guide to IOS 15.0(2)SE11 If you're still running a Cisco Catalyst 3560 series switch
Microcode Upgrades: When booting this version for the first time, the switch may perform internal microcode updates for components like the PoE controller. This can cause the initial boot to take 10–30 minutes; do not power off the device during this period. C3560-ipservicesk9-mz.150-2.se11.bin
mz: This tells you where the file runs and its compression. "m" means it runs from RAM, and "z" means the file is zip-compressed to save flash memory space. Updating Your Cisco Catalyst 3560: A Guide to IOS 15
no ipv6 mld snooping if IPv6 is unused.snmp-server ifindex persist.