Brocade (now owned by Ruckus) switches have two versions of code loaded by default to two different partitions. The primary partition contains a layer 2 image, while the secondary partition contains a layer 3 image. For the ICX-6610 switches, the layer 2 image is named FCXSxxxxx.bin and the layer 3 image is named FCXRxxxxx.bin. Notice the S and R to notate layer 2 (switching) and layer 3 (routing), respectively. In order to enable layer 3 features on an ICX-6610 switch, you must switch to the layer 3 image by updating the boot record. You can see the following link for more information: https://community.brocade.com/t5/Ethernet-Switches-Routers/FastIron-image-files-and-choosing-Layer-2-or-Layer-3-code/ta-p/2887
Also, you are able to update these switches using a manifest file, which allows it to do most of the update for you. Using the manifest file will only update the running code version. To update the non-running code, you can use TFTP.
Brocade has recently sold their product lines to several companies. The product line for larger equipment was purchased by Broadcom and the brocade.com website can still be used for information for these devices. The product line for smaller equipment (what most of our customers own) was sold to Ruckus and information/downloads can only be found on the ruckuswireless.com website.