Hello,
In common there is no issue to connect different switches from different vendors by optics (via SFP or SFP+) as long as they support same physical conditions (wavelength and so on). You can check Cisco SFP / SFP+ Data Sheet here:
https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/gigabit-ethernet-gbic-sfp-modules/product_data_sheet0900aecd8033f885.html
Also, during trunk auto-negotiation process switches may fail to form a trunk link because of vendor issues, so I would rather disable this auto-negotiation with switchport nonegotiate . Also as per Cisco best practice manual speed and duplex should be defined on ports to achieve maximum and predictable performance.
However you need to ensure that:
- Both switches are using same STP mode
- Both switches have their ports configured as trunks
- Both switches have same VLAN IDs configured
- Both switches have same native VLAN ID
I would go with the following configuration on Cisco switch:
interface X/X/X
switchport mode trunk
switchport trunk native vlan X
switchport nonegotiate
speed X
duplex full
switchport trunk encapsulation dot11q
Last command may not be applicable to your switch due to Cisco has depreciated ISL trunking and stick to dot11q encapsulation as default and only one available option.
Also after you see that traffic can pass between this two devices I would monitor situation a bit with show interface X/X command to ensure that there is no errors or CRC.
