RESILENT LINKS: SW4WHT failure recovery

This device gives connectivity to CASS, GRACE, GRHIL, ROBODIMM, autoguiders and other network sockets in the control room of the WHT as well as the wireless network in that area. Is located in the blue cabinets by the WHT fire alarm control panel.

If this device fails, major problems will occur in the WHT observing system. The connectivity will be lost with the autoguiders, instruments in all the focal stations and ICS.

Before following the next steps is a good idea to power cycle sw4wht to see if that fixes the problem.

The spare for this device is sw11wht, below it, and the procedure to use it instead of sw4wht is as follows:

1. Switch off sw4wht.

2. Move front UTP cables from sw4wht to sw11wht as described in this table:

   From	To
   sw4wht 1	sw11wht 1
   sw4wht 2	sw11wht 2
   sw4wht 3	sw11wht 3
   sw4wht 4	sw11wht 4
   sw4wht 5	sw11wht 5
   sw4wht 6	sw11wht 6
   sw4wht 7	sw11wht 7
   sw4wht 8	sw11wht 8
   sw4wht 9	sw11wht 9
   sw4wht 10	sw11wht 10
   sw4wht 11	sw11wht 11
   sw4wht 12	sw11wht 12
   sw4wht 13	sw11wht 13
   sw4wht 14	sw11wht 14
   sw4wht 15	sw11wht 15
   sw4wht 16	sw11wht 16
   sw4wht 17	sw11wht 17
   sw4wht 18	sw11wht 18
   sw4wht 19	sw11wht 19
   sw4wht 20	sw11wht 20
   sw4wht 21	sw11wht 21
   sw4wht 23	sw11wht 23

3. Move the fiber in the back of sw4wht to sw11wht

After this is done, it takes a few minutes for the network to come back again.

Any question regarding this document, contact Luis Hernandez