I have sw1 for core-switch. and sw2 for standby. both are multi-layer switches.
As I know , to make dualism, need to use HSRP. My question is that Can I use HSRP in Multi-layer switches? or is it only functioned in Router? Do you know good way to make dualism?
yes you can use HSRP on multilayer switches we do it on all our campus networks.
However, there is one important note about HSRP implementation that needs to be taken in account:
in routers Vlan based subinterfaces like fas0/0.100, fas0/0.110 and so on require to use different HSRP group number on each of them.
Multilayer switches can use the same HSRP group on multiple SVI Vlan interfaces.
Actually for multilayer switches this is a scalability feature: with the exception of C6500 other platforms can support a low number of HSRP group numbers for example 16 but allow to reuse them as needed:
so you can have 16 different groups but used in 160 different Vlans.
Multilayer switches are able to track on what vlan a packet is received.
Depending on the platform if supported you may also consider GLBP that provides effective load balancing for vlans where multiple clients are present
Hope to help