01/23 10:05:15.269 WARNI|       ping_runner:0352| Ping command returned no output; stderr was ping: unknown host chromeos1-grover-host4-pcap
.
01/23 10:05:15.271 DEBUG|             utils:0214| Running 'ping -c 3 -i 0.500000 chromeos1-grover-host4-attenuator'
01/23 10:05:16.420 INFO |attenuator_control:0214| Configuring GPIO ports on attenuator host.
01/23 10:05:16.440 DEBUG|          ssh_host:0301| Running (ssh) 'echo 7 > /sys/kernel/debug/omap_mux/gpmc_csn2' from 'warmup|setup|__init__|_enable_gpio_pin|run|run_very_slowly'
01/23 10:05:16.598 ERROR|             utils:0282| [stderr] ssh: connect to host chromeos1-grover-host4-attenuator port 22: Connection refused
01/23 10:05:16.608 WARNI|              test:0637| The test failed with the following exception
Traceback (most recent call last):
  File "/usr/local/autotest/client/common_lib/test.py", line 618, in _exec
    *args, **dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 837, in _call_test_function
    raise error.UnhandledTestFail(e)
UnhandledTestFail: Unhandled AutoservRunError: command execution error
* Command: 
    /usr/bin/ssh -a -x   -o StrictHostKeyChecking=no -o
    UserKnownHostsFile=/tmp/tmpCh7cKt -o BatchMode=yes -o ConnectTimeout=30 -o
    ServerAliveInterval=300 -o ServerAliveCountMax=3 -o ConnectionAttempts=1
    -l root -p 22 chromeos1-grover-host4-attenuator " if type \"logger\" >
    /dev/null 2>&1; then logger -tag \"autotest\"
    \"server[stack::__init__|_enable_gpio_pin|run] -> ssh_run(echo 7 >
    /sys/kernel/debug/omap_mux/gpmc_csn2)\";fi; echo 7 >
    /sys/kernel/debug/omap_mux/gpmc_csn2"
Exit status: 255
Duration: 0.108641862869

stderr:
ssh: connect to host chromeos1-grover-host4-attenuator port 22: Connection refused
Traceback (most recent call last):
  File "/usr/local/autotest/client/common_lib/test.py", line 831, in _call_test_function
    return func(*args, **dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 746, in _cherry_pick_call
    return func(*p_args, **p_dargs)
  File "/usr/local/autotest/server/cros/network/wifi_cell_test_base.py", line 84, in warmup
    self._wifi_context.setup()
  File "/usr/local/autotest/server/cros/network/wifi_test_context_manager.py", line 214, in setup
    hosts.SSHHost(attenuator_addr, port=22))
  File "/usr/local/autotest/server/cros/network/attenuator_controller.py", line 217, in __init__
    self._enable_gpio_pin(gpio_pin)
  File "/usr/local/autotest/server/cros/network/attenuator_controller.py", line 253, in _enable_gpio_pin
    self._host.run('echo 7 > %s' % gpio_pin.pinmux_file)
  File "/usr/local/autotest/server/hosts/ssh_host.py", line 323, in run
    return self.run_very_slowly(*args, **kwargs)
  File "/usr/local/autotest/server/hosts/ssh_host.py", line 312, in run_very_slowly
    ssh_failure_retry_ok)
  File "/usr/local/autotest/server/hosts/ssh_host.py", line 262, in _run
    raise error.AutoservRunError("command execution error", result)
AutoservRunError: command execution error
* Command: 
    /usr/bin/ssh -a -x   -o StrictHostKeyChecking=no -o
    UserKnownHostsFile=/tmp/tmpCh7cKt -o BatchMode=yes -o ConnectTimeout=30 -o
    ServerAliveInterval=300 -o ServerAliveCountMax=3 -o ConnectionAttempts=1
    -l root -p 22 chromeos1-grover-host4-attenuator " if type \"logger\" >
    /dev/null 2>&1; then logger -tag \"autotest\"
    \"server[stack::__init__|_enable_gpio_pin|run] -> ssh_run(echo 7 >
    /sys/kernel/debug/omap_mux/gpmc_csn2)\";fi; echo 7 >
    /sys/kernel/debug/omap_mux/gpmc_csn2"
Exit status: 255
Duration: 0.108641862869

stderr:
ssh: connect to host chromeos1-grover-host4-attenuator port 22: Connection refused

Updates
1) The ssh service on (chromeos1-grover-host4 and chromeos1-grover-host8) attenuators is running. Also, added a cronjob to restart the service if it goes down. 

2) For the router @ chromeos1-grover-host3, I was able to power it on but it looks like os image is corrupted. Will check on this later. 

3) Will monitor chell results. Infra wise it looks good.