text: **13.1.2 Expansion canisters**
  
  As Figure 13-2 shows, two 12 Gbps SAS ports are side by side on the canister of every 
  enclosure. They are numbered 1 on the left and 2 on the right. Similar to the controller 
  canisters, expansion canisters are also installed in the enclosure side by side in a vertical 
  position. 
  
  **Canister LEDs**
  - green left: power 
  - green horse-shoe: status 
  - amber: fault 
  **SAS Indicators**
  - green: link 
  - amber: fault 