This is super easy.

You can use Maya’s UDIM system (turn on UDIM in the File nodes: UV Tiling Mode -> UDIM).

Update (2021)

Use the rsBumpMap node!
It understands the simple file node connection therefore works with UDIM as well.
Of course change the input type to Tangent-Sapce Normal for normal maps.

Cheers, D

Original Post from 2017:
Unfortunately there is no UDIM option in Redshift’s custom normal map node (RedshiftNormalMap), but you can still use the <UDIM> naming convention by typing it manually. After you linked the first image just change the number to <UDIM>.

That’s all.

Cheers, D

Useful tip for texture connections:

In Redshift you can also use file nodes for Normal maps, Dome Map (rsDomeLight) and other non Maya’s file node based links:

• Create the file node
• Load your image
• Connect the fileTextureName attribute to tex0 attribute

Simple way to do that is via the Connection Editor: in Hypershade, Shift + MMB Drag and Drop the file node into the other node’s header part).