Similar issue.
FAS3250> [FAS3250:cf.ic.qlgc.viErr:error]: Qlogic VI FC Adapter: ISP_CS_VI_ERROR vinum = 0x3 state = 0x3 code = 0x6
FAS3250> [FAS3250:sm.fcvi.adapterReset:warning]: Initiating soft reset on FCVI adapter in slot 2b due to ispfcvi2400 fatal VI error
Replication between storages which are very close to each other is ok, but for long distance very low speed. What problem can it be?