Paul,

Yes, you can define multiple IPAQENET INTERFACE statements for the same physical OSA (OSD) card / port using Portname which points to a user defined TRLE. The TRLE will require enough data devices (2 for read/write control + 1 for every interface statement used by the z/OS instance), in case you run with multiple stacks. For example, if you need 4 INTERFACE statements, then you need at least 6 devices in the TRLE. You also need one additional device if you plan to run NTA (OSA sniffer).  Multiple interface statements for the same OSA requires: 1. Unique VLAN IDs 2. unique IP addresses 3.  each must have a unique subnet mask 4. all must be configured with VMAC (recommend OSA generated) and RouteALL (default). The physical switch port must be configured in trunk mode matching the VLAN IDs defined on the interface statements. Note that when the switch is in access mode z/OS is unaware of VLANs (will not tag or filter). In trunk mode the OS will tag outbound and filter inbound. Also note that when you use portname for a specific OSA, all interfaces in all stacks in all LPARs must use the same portname. Linux does not use portname.  Hope this helps.

Paul,

Yes, you can define multiple IPAQENET INTERFACE statements for the same physical OSA (OSD) card / port using Portname which points to a user defined TRLE. The TRLE will require enough data devices (2 for read/write control + 1 for every interface statement used by the z/OS instance), in case you run with multiple stacks. For example, if you need 4 INTERFACE statements, then you need at least 6 devices in the TRLE. You also need one additional device if you plan to run NTA (OSA sniffer).  Multiple interface statements for the same OSA requires: 1. Unique VLAN IDs 2. unique IP addresses 3.  each must have a unique subnet mask 4. all must be configured with VMAC (recommend OSA generated) and RouteALL (default). The physical switch port must be configured in trunk mode matching the VLAN IDs defined on the interface statements. Note that when the switch is in access mode z/OS is unaware of VLANs (will not tag or filter). In trunk mode the OS will tag outbound and filter inbound. Also note that when you use portname for a specific OSA, all interfaces in all stacks in all LPARs must use the same portname. Linux does not use portname.  Hope this helps.

1. unique IP subnets which are defined by the mask bits (subnet mask or slash after the ip address), defined on the INTERFACE statement as "ipv4_address/num_mask_bits"
   
2. your IP addresses are so similar they appear to be within the same subnet... (or very small subnets) the IP Addresses must be unique and come from unique subnets (defined by your mask)
3. your VLAN IDs must be unique (you have 4 on both). The VLAN IDs (e.g. 4 and 5) must be configured on the switch port (in trunk mode). 
4. NONROUTER is invalid. PRI/SEC/NONROUTER only applies when NOT using VMAC. When using VMAC (required for multiple interfaces) then ROUTEALL/ROUTELOCAL replaces PRI/SEC/NONROUTER.  VMAC ROUTEALL is ok as is.
5. You don't need to define MTU (you seem to have two values) unless you need to override the OSA default (jumbo). 1492 might be safer to use if not sure. Note that MTU from the IP route will override this value (OMPRoute or static). 

Paul,

Yes, you can define multiple IPAQENET INTERFACE statements for the same physical OSA (OSD) card / port using Portname which points to a user defined TRLE. The TRLE will require enough data devices (2 for read/write control + 1 for every interface statement used by the z/OS instance), in case you run with multiple stacks. For example, if you need 4 INTERFACE statements, then you need at least 6 devices in the TRLE. You also need one additional device if you plan to run NTA (OSA sniffer).  Multiple interface statements for the same OSA requires: 1. Unique VLAN IDs 2. unique IP addresses 3.  each must have a unique subnet mask 4. all must be configured with VMAC (recommend OSA generated) and RouteALL (default). The physical switch port must be configured in trunk mode matching the VLAN IDs defined on the interface statements. Note that when the switch is in access mode z/OS is unaware of VLANs (will not tag or filter). In trunk mode the OS will tag outbound and filter inbound. Also note that when you use portname for a specific OSA, all interfaces in all stacks in all LPARs must use the same portname. Linux does not use portname.  Hope this helps.