This Gauge32 is the chassis number associated with the object on the far end of this internal backplane link. It matters on the internal Ethernet link that carries a blade's traffic from the chassis I/O Module up to a Fabric Interconnect over the backplane because for this particular internal link type the peer is the fabric interconnect side rather than another chassis, so this field is mainly useful for confirming the link's topology is wired to the chassis an admin expects. A peerChassisId value on this backplane link that doesn't match chassisId 4 on the same object would be worth double-checking against the physical cabling diagram for that chassis.