WLAN environment are becoming crutial for services in a company, therefor upgrading the AC without an interruption is becoming a need for everycompany which runs WLAN.Here I will intrdocue in-service software upgrade.An ISSU(in-service software upgrade) is a technique for updating software on a network device without disruption the network service. In-service softeare upgrades allow a network operator to address software bugs and add new features without interrupting network availability.
For the AC ISSU upgrade function, the 2 ACs should work in VRRP HSB status.When user set the next startup system file in AC, the system will enable the ISSU function by default. User can select the hitless restart option. Please upgrade the backup AC first, then after backup AC finish upgrade, upgrade the Master AC. During the process for ISSU upgrade, the AP will keep managed by the AC and no need go online again which can provide the non-interruption WLAN service.
1. Upgrade Backup AC
Set the next startup system file and upload the version
Select hitless restart
After upgrade finish, check the current version for backup AC
Upgrade Master AC (After backup AC finish upgrade)
Set the next startup system file and upload the version(follow the same procedure as upgrading the standby AC)
after upgrading, check the version.