-pcap Network Type 276 Unknown Or Unsupported-

Run capinfos (from Wireshark) on the offending file:

Download the latest "Stable Release" from the official Wireshark website. -pcap network type 276 unknown or unsupported-

Check the global header. In a standard pcap, bytes 20-23 contain the link-layer header type (little-endian). For DLT 276, you will see: 0x14 0x01 0x00 0x00 (since 276 decimal = 0x0114 hex). Run capinfos (from Wireshark) on the offending file:

According to standard libpcap references, link type 276 is defined as [Insert Protocol Name if known, otherwise "currently unassigned/proprietary"] . This prevents the analysis of traffic from [Device Name]. Is it possible to add support for this link type? For DLT 276, you will see: 0x14 0x01

(LINKTYPE_SCLIB) is a specific data link type used by Cisco Systems for internal diagnostic packet captures, particularly on Nexus and ACI platforms.

If you cannot upgrade your viewing tool, you can try to force the capture tool to use the older "cooked" v1 format (LINKTYPE_LINUX_SLL), though this depends on the specific tool's supported arguments.