text: **13.1.1 Node canisters**
  
  Two node canisters are contained in the control enclosure that work as a clustered system 
  running the IBM Spectrum Virtualize software. Figure 13-1 shows the ports and indicator 
  lights of a node canister, with the Front Panel LEDs providing a convenient status summary. 
  The second canister is placed next to the first one in a side-by-side configuration. 
  
  **SAS Indicators**
  - green: link 
  - amber: fault 
  **Canister LEDs**
  - green left: power 
  - green horse-shoe: status 
  - amber: fault 
  **Battery LEDs**
  - green: status 
  - amber: fault 
  
  **Host Interface Cards**