Hi,
We have recently replaced a pair of legacy distribution switches (WS-C3750X-12S-E) with a pair of 9300's (C9300-24S-A). The config is identical, and so are the SFP's (and are compatible with this unit). The access switch downstream (WS-C3560X-48) has two up links - one for each distribution - and was working fine with the old switches. when we replaced the distribution with the 9300's - we saw loop back errors on the access switch and some inconsistent vlans, this forced both uplinks into error disabled state. after doing a shut and no shut on both interfaces - everything worked perfectly fine. we believe that this may have occurred because of spanning-tree incompatibilities between the 9300's and the access switch. can anybody confirm if this is possible, or what could have caused this issue ?
a diagram of the set-up has been drawn bellow:
--------[9300-dist01]
[3560x]----[
--------[9300-dist02]
Best Regards,
Sabeel