Check Accessibility Control

This scenario shows how to configure a cellular interface, enabling the accessibility control mechanism that triggers reconnections when network connectivity is lost.

../../../../_images/google.svg

Test Reconnection By Accessibility Control

Description

In DUT0, the cell0 cellular interface is configured with a cellular profile for which accessibility control is enabled. Once connectivity with Google’s DNS public server has been verified, a situation where 100% of the packets received by the network are lost is emulated to verify that the accessibility control mechanism triggers a reconnection.

Scenario

Step 1: Set the following configuration in DUT0 :

set cellular logging level info
set cellular profile CELPROFILE accessibility-control ping address 8.8.8.8
set cellular profile CELPROFILE accessibility-control ping interval 10
set cellular profile CELPROFILE apn movistar.es
set controllers cellular wwan0 encrypted-pin U2FsdGVkX19pJTpklucpehYomQonAjmmkoE4rqrlhM4=
set controllers cellular wwan0 pdp 1 profile CELPROFILE
set interfaces cellular cell0 address dhcp
set interfaces cellular cell0 phy wwan0 pdp 1
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Run command controllers cellular wwan0 pdp 1 show network-data-connection at DUT0 and check if output matches the following regular expressions:

Connection status\s* = connected
Show output
Connection status               = connected
Traffic channel status          = active
Max. TX channel rate (bps)      = 50000000
Max. RX channel rate (bps)      = 300000000
IPv4 address                    = 5.205.199.196
IPv4 mask                       = 255.255.255.248
IPv4 gateway                    = 5.205.199.197
IPv4 primary DNS                = 80.58.61.248
IPv4 secondary DNS              = 80.58.61.249

Note

Once the cellular interface is configured, it can be verified that there is network connectivity by pinging Google's DNS public server.

Step 3: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=118 time=25.5 ms

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 25.482/25.482/25.482/0.000 ms

Note

The accessibility control is a mechanism where pings are sent at an interval, and to the IP address, configured by the user. The mechanism then waits for a response within this interval. If no response is received before it times out, a second ping is sent and a response is expected within 10 seconds. If there is still no response, two more pings are sent at 5-second intervals. Finally, if there is still no response, the device reconnects to the network.

Note

As a result, you can verify that no reconnection has been recorded in the system logs if you wait long enough.

Step 4: Run command system journal clear at DUT0.

Step 5: Run command system journal show | cat at DUT0 and check if output does not contain the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 17 00:03:30.291250 osdx systemd-journald[474284]: Runtime Journal (/run/log/journal/9a1c6a3338f7494eb1f93926026954fa) is 8.2M, max 80.5M, 72.2M free.
Apr 17 00:03:30.298416 osdx systemd-journald[474284]: Received client request to rotate journal, rotating.
Apr 17 00:03:30.298602 osdx systemd-journald[474284]: Vacuuming done, freed 0B of archived journals from /run/log/journal/9a1c6a3338f7494eb1f93926026954fa.
Apr 17 00:03:30.396047 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal clear'.
Apr 17 00:03:39.392943 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Previous packet pending - ID: 47324, Sequence: 0
Apr 17 00:03:39.392963 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds

Note

However, when traffic control is applied, it is possible to prove the 'ping' command is failing because ICMP packets are being dropped.

Step 6: Run command system journal clear at DUT0.

Step 7: Modify the following configuration lines in DUT0 :

set interfaces cellular cell0 traffic control in PLOSS
set traffic control PLOSS type network-emulator packet-loss 100

Step 8: Expect a failure in the following command: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms

Note

You can verify that a reconnection has been recorded in the system logs if you wait long enough.

Step 9: Run command system journal show | cat at DUT0 and check if output contains the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 17 00:04:12.723939 osdx systemd-journald[474284]: Runtime Journal (/run/log/journal/9a1c6a3338f7494eb1f93926026954fa) is 8.0M, max 80.5M, 72.5M free.
Apr 17 00:04:12.731333 osdx systemd-journald[474284]: Received client request to rotate journal, rotating.
Apr 17 00:04:12.731521 osdx systemd-journald[474284]: Vacuuming done, freed 0B of archived journals from /run/log/journal/9a1c6a3338f7494eb1f93926026954fa.
Apr 17 00:04:12.816055 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal clear'.
Apr 17 00:04:12.983875 osdx OSDxCLI[626364]: User 'admin' entered the configuration menu.
Apr 17 00:04:13.102244 osdx OSDxCLI[626364]: User 'admin' added a new cfg line: 'set interfaces cellular cell0 traffic control in PLOSS'.
Apr 17 00:04:13.204645 osdx OSDxCLI[626364]: User 'admin' added a new cfg line: 'set traffic control PLOSS type network-emulator packet-loss 100'.
Apr 17 00:04:13.331959 osdx OSDxCLI[626364]: User 'admin' added a new cfg line: 'show changes'.
Apr 17 00:04:13.477469 osdx ubnt-cfgd[637243]: inactive
Apr 17 00:04:13.603567 osdx INFO[637253]: FRR daemons did not change
Apr 17 00:04:13.708095 osdx (udev-worker)[637273]: ifb.cell0: Could not set Alias=, MACAddress=/MACAddressPolicy=, TransmitQueues=, ReceiveQueues=, TransmitQueueLength=, MTUBytes=, GenericSegmentOffloadMaxBytes= or GenericSegmentOffloadMaxSegments=, ignoring: Operation not supported
Apr 17 00:04:13.708193 osdx (udev-worker)[637273]: Network interface NamePolicy= disabled on kernel command line.
Apr 17 00:04:13.723457 osdx cfgd[1735]: [626364]Completed change to active configuration
Apr 17 00:04:13.752201 osdx systemd[1]: osdx-ledsd.service: Sent signal SIGUSR2 to main process 2407 (osdx-ledsd) on client request.
Apr 17 00:04:13.752252 osdx osdx-ledsd[2407]: Config changed, checking config paths
Apr 17 00:04:13.756272 osdx OSDxCLI[626364]: User 'admin' committed the configuration.
Apr 17 00:04:13.794512 osdx OSDxCLI[626364]: User 'admin' left the configuration menu.
Apr 17 00:04:15.048852 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'ping 8.8.8.8 count 1 size 56 timeout 1'.
Apr 17 00:04:29.393998 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Previous packet pending - ID: 47324, Sequence: 5
Apr 17 00:04:29.394015 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds
Apr 17 00:04:35.386083 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:36.722091 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:38.078088 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:39.394271 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Previous packet pending - ID: 47324, Sequence: 6
Apr 17 00:04:39.394296 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 2 - interval reduced to 5 seconds
Apr 17 00:04:39.462054 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:40.858068 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:42.274087 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:43.714100 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:44.394552 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Previous packet pending - ID: 47324, Sequence: 7
Apr 17 00:04:44.394570 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 3 - interval reduced to 5 seconds
Apr 17 00:04:45.182071 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:46.678083 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:48.154084 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:49.394831 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Previous packet pending - ID: 47324, Sequence: 8
Apr 17 00:04:49.394851 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 4 - interval reduced to 5 seconds
Apr 17 00:04:49.407155 osdx WARNING[637382]: [wwan0/1] Requesting reconnection...
Apr 17 00:04:49.416471 osdx wwan-cli-socket[637384]: [Device/wwan0] Info: wwan-cli-socket reconnect 60000 wwan0
Apr 17 00:04:49.417077 osdx wwan-module[626349]: [Device/wwan0] Info: Reconnecting device...
Apr 17 00:04:49.417094 osdx wwan-module[626349]: [Device/wwan0] Warning: [PDP#1] Requesting reconnection...
Apr 17 00:04:49.417182 osdx wwan-module[626349]: [Device/wwan0] Info: WDS[0]: Stopping network connection...
Apr 17 00:04:49.525630 osdx wwan-module[626349]: [Device/wwan0] Info: WDS[0]: Network connection was stopped!
Apr 17 00:04:49.533732 osdx kernel: net _wwan0: link_state 0x1 -> 0x0
Apr 17 00:04:49.534618 osdx wwan-module[626349]: [Device/wwan0] Info: Checking registration state...
Apr 17 00:04:49.564900 osdx wwan-accessibility-control[637148]: [Core/wwan0/1] Info: Execution stopped
Apr 17 00:04:49.565750 osdx systemd[1]: Stopping wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control...
Apr 17 00:04:49.568161 osdx systemd[1]: wwan-accessibility-control@wwan0pdp1.service: Deactivated successfully.
Apr 17 00:04:49.568777 osdx systemd[1]: Stopped wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control.
Apr 17 00:04:49.585300 osdx INFO[637390]: Stop DHCP client for cell0
Apr 17 00:04:49.595225 osdx dhclient[637395]: Killed old client process
Apr 17 00:04:49.642025 osdx OSDxCLI[626364]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 17 00:04:49.653654 osdx wwan-module[626349]: [Device/wwan0] Info: Device registered and PS attached successfully
Apr 17 00:04:49.653670 osdx wwan-module[626349]: [Device/wwan0] Info: [PDP#1] Establishing network connection...
Apr 17 00:04:49.717019 osdx dhclient[637395]: DHCPRELEASE of 5.205.199.196 on cell0 to 5.205.199.197 port 67
Apr 17 00:04:49.854550 osdx wwan-module[626349]: [Device/wwan0] Info: [PDP#1] Network connection was successfully started: PDH=[708046432]
Apr 17 00:04:49.976781 osdx kernel: net _wwan0: link_state 0x0 -> 0x1
Apr 17 00:04:50.244772 osdx kernel: cell0: (slave _wwan0_1): Releasing backup interface
Apr 17 00:04:50.460773 osdx kernel: cell0: (slave _wwan0_1): The slave device specified does not support setting the MAC address
Apr 17 00:04:50.464809 osdx kernel: cell0: (slave _wwan0_1): making interface the new active one
Apr 17 00:04:50.465005 osdx kernel: cell0: (slave _wwan0_1): Enslaving as an active interface with an up link
Apr 17 00:04:50.480774 osdx kernel: 8021q: adding VLAN 0 to HW filter on device cell0
Apr 17 00:04:50.483771 osdx INFO[637445]: Start DHCP client for cell0

Step 1: Set the following configuration in DUT0 :

set cellular logging level info
set cellular profile CELPROFILE accessibility-control ping address 8.8.8.8
set cellular profile CELPROFILE accessibility-control ping interval 10
set cellular profile CELPROFILE apn movistar.es
set controllers cellular wwan0 sim select socket_1
set controllers cellular wwan0 sim socket socket_1 encrypted-pin U2FsdGVkX18Qpl4KV30C9jXoofn02DB60vJma/0neDU=
set controllers cellular wwan0 sim socket socket_1 pdp 1 profile CELPROFILE
set interfaces cellular cell0 address dhcp
set interfaces cellular cell0 phy wwan0 pdp 1
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Run command controllers cellular wwan0 pdp 1 show network-data-connection at DUT0 and check if output matches the following regular expressions:

Connection status\s* = connected
Show output
Connection status               = connected
Traffic channel status          = active
Max. TX channel rate (bps)      = 0
Max. RX channel rate (bps)      = 0
IPv4 address                    = 88.31.51.76
IPv4 mask                       = 255.255.255.248
IPv4 gateway                    = 88.31.51.77
IPv4 primary DNS                = 80.58.61.248
IPv4 secondary DNS              = 80.58.61.249

Note

Once the cellular interface is configured, it can be verified that there is network connectivity by pinging Google's DNS public server.

Step 3: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=117 time=31.0 ms

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 30.954/30.954/30.954/0.000 ms

Note

The accessibility control is a mechanism where pings are sent at an interval, and to the IP address, configured by the user. The mechanism then waits for a response within this interval. If no response is received before it times out, a second ping is sent and a response is expected within 10 seconds. If there is still no response, two more pings are sent at 5-second intervals. Finally, if there is still no response, the device reconnects to the network.

Note

As a result, you can verify that no reconnection has been recorded in the system logs if you wait long enough.

Step 4: Run command system journal clear at DUT0.

Step 5: Run command system journal show | cat at DUT0 and check if output does not contain the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 16 22:31:08.258195 osdx systemd-journald[809299]: Runtime Journal (/run/log/journal/dbae3d0590e14adfb1d3984742dc8c6b) is 8.0M, max 69.4M, 61.4M free.
Apr 16 22:31:08.259669 osdx systemd-journald[809299]: Received client request to rotate journal, rotating.
Apr 16 22:31:08.259722 osdx systemd-journald[809299]: Vacuuming done, freed 0B of archived journals from /run/log/journal/dbae3d0590e14adfb1d3984742dc8c6b.
Apr 16 22:31:08.312672 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal clear'.
Apr 16 22:31:11.652537 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Previous packet pending - ID: 8517, Sequence: 0
Apr 16 22:31:11.652543 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds

Note

However, when traffic control is applied, it is possible to prove the 'ping' command is failing because ICMP packets are being dropped.

Step 6: Run command system journal clear at DUT0.

Step 7: Modify the following configuration lines in DUT0 :

set interfaces cellular cell0 traffic control in PLOSS
set traffic control PLOSS type network-emulator packet-loss 100

Step 8: Expect a failure in the following command: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms

Note

You can verify that a reconnection has been recorded in the system logs if you wait long enough.

Step 9: Run command system journal show | cat at DUT0 and check if output contains the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 16 22:31:50.594040 osdx systemd-journald[809299]: Runtime Journal (/run/log/journal/dbae3d0590e14adfb1d3984742dc8c6b) is 8.0M, max 69.4M, 61.4M free.
Apr 16 22:31:50.595508 osdx systemd-journald[809299]: Received client request to rotate journal, rotating.
Apr 16 22:31:50.595567 osdx systemd-journald[809299]: Vacuuming done, freed 0B of archived journals from /run/log/journal/dbae3d0590e14adfb1d3984742dc8c6b.
Apr 16 22:31:50.648662 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal clear'.
Apr 16 22:31:50.782359 osdx OSDxCLI[982002]: User 'admin' entered the configuration menu.
Apr 16 22:31:50.867356 osdx OSDxCLI[982002]: User 'admin' added a new cfg line: 'set interfaces cellular cell0 traffic control in PLOSS'.
Apr 16 22:31:50.978276 osdx OSDxCLI[982002]: User 'admin' added a new cfg line: 'set traffic control PLOSS type network-emulator packet-loss 100'.
Apr 16 22:31:51.090956 osdx OSDxCLI[982002]: User 'admin' added a new cfg line: 'show changes'.
Apr 16 22:31:51.215242 osdx ubnt-cfgd[991653]: inactive
Apr 16 22:31:51.253862 osdx INFO[991663]: FRR daemons did not change
Apr 16 22:31:51.278914 osdx (udev-worker)[991681]: ifb.cell0: Could not set Alias=, MACAddress=/MACAddressPolicy=, TransmitQueues=, ReceiveQueues=, TransmitQueueLength=, MTUBytes=, GenericSegmentOffloadMaxBytes= or GenericSegmentOffloadMaxSegments=, ignoring: Operation not supported
Apr 16 22:31:51.278943 osdx (udev-worker)[991681]: Network interface NamePolicy= disabled on kernel command line.
Apr 16 22:31:51.286334 osdx cfgd[2019]: [982002]Completed change to active configuration
Apr 16 22:31:51.289563 osdx OSDxCLI[982002]: User 'admin' committed the configuration.
Apr 16 22:31:51.353186 osdx OSDxCLI[982002]: User 'admin' left the configuration menu.
Apr 16 22:31:52.516874 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'ping 8.8.8.8 count 1 size 56 timeout 1'.
Apr 16 22:32:01.653147 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Previous packet pending - ID: 8517, Sequence: 5
Apr 16 22:32:01.653155 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds
Apr 16 22:32:11.653315 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Previous packet pending - ID: 8517, Sequence: 6
Apr 16 22:32:11.653321 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 2 - interval reduced to 5 seconds
Apr 16 22:32:12.843950 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:14.151945 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:15.487943 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:16.653456 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Previous packet pending - ID: 8517, Sequence: 7
Apr 16 22:32:16.653464 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 3 - interval reduced to 5 seconds
Apr 16 22:32:16.819945 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:18.235939 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:19.619954 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:21.003939 osdx OSDxCLI[982002]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 22:32:21.653597 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Previous packet pending - ID: 8517, Sequence: 8
Apr 16 22:32:21.653604 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 4 - interval reduced to 5 seconds
Apr 16 22:32:21.657195 osdx WARNING[991771]: [wwan0/1] Requesting reconnection...
Apr 16 22:32:21.659968 osdx wwan-cli-socket[991773]: [Device/wwan0] Info: wwan-cli-socket reconnect 60000 wwan0
Apr 16 22:32:21.660224 osdx wwan-module[2511]: [Device/wwan0] Info: Reconnecting device...
Apr 16 22:32:21.660231 osdx wwan-module[2511]: [Device/wwan0] Warning: [PDP#1] Requesting reconnection...
Apr 16 22:32:21.660318 osdx wwan-module[2511]: [Device/wwan0] Info: WDS[0]: Stopping network connection...
Apr 16 22:32:21.763178 osdx wwan-module[2511]: [Device/wwan0] Info: WDS[0]: Network connection was stopped!
Apr 16 22:32:21.767519 osdx kernel: net _wwan0: link_state 0x1 -> 0x0
Apr 16 22:32:21.768706 osdx wwan-module[2511]: [Device/wwan0] Info: Checking registration state...
Apr 16 22:32:21.773908 osdx systemd[1]: Stopping wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control...
Apr 16 22:32:21.773926 osdx wwan-accessibility-control[991557]: [Core/wwan0/1] Info: Execution stopped
Apr 16 22:32:21.774579 osdx systemd[1]: wwan-accessibility-control@wwan0pdp1.service: Deactivated successfully.
Apr 16 22:32:21.774727 osdx systemd[1]: Stopped wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control.
Apr 16 22:32:21.778386 osdx INFO[991777]: Stop DHCP client for cell0
Apr 16 22:32:21.782662 osdx dhclient[991784]: Killed old client process
Apr 16 22:32:21.827004 osdx wwan-module[2511]: [Device/wwan0] Info: Device registered and PS attached successfully
Apr 16 22:32:21.827011 osdx wwan-module[2511]: [Device/wwan0] Info: [PDP#1] Establishing network connection...
Apr 16 22:32:21.931644 osdx dhclient[991784]: DHCPRELEASE of 88.31.51.76 on cell0 to 88.31.51.77 port 67
Apr 16 22:32:22.083999 osdx wwan-module[2511]: [Device/wwan0] Info: [PDP#1] Network connection was successfully started: PDH=[3799041648]
Apr 16 22:32:22.091521 osdx kernel: cell0: (slave _wwan0_1): Releasing backup interface

Step 1: Set the following configuration in DUT0 :

set cellular logging level info
set cellular profile CELPROFILE accessibility-control ping address 8.8.8.8
set cellular profile CELPROFILE accessibility-control ping interval 10
set cellular profile CELPROFILE apn movistar.es
set controllers cellular wwan0 sim select socket_1
set controllers cellular wwan0 sim socket socket_1 encrypted-pin U2FsdGVkX19dytQiFF5UpvP0q/eTByiKaYVS1VQj+mg=
set controllers cellular wwan0 sim socket socket_1 pdp 1 profile CELPROFILE
set interfaces cellular cell0 address dhcp
set interfaces cellular cell0 phy wwan0 pdp 1
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Run command controllers cellular wwan0 pdp 1 show network-data-connection at DUT0 and check if output matches the following regular expressions:

Connection status\s* = connected
Show output
Connection status               = connected
Traffic channel status          = active
Max. TX channel rate (bps)      = 0
Max. RX channel rate (bps)      = 0
IPv4 address                    = 5.205.233.22
IPv4 mask                       = 255.255.255.252
IPv4 gateway                    = 5.205.233.21
IPv4 primary DNS                = 80.58.61.248
IPv4 secondary DNS              = 80.58.61.249

Note

Once the cellular interface is configured, it can be verified that there is network connectivity by pinging Google's DNS public server.

Step 3: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=118 time=160 ms

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 159.659/159.659/159.659/0.000 ms

Note

The accessibility control is a mechanism where pings are sent at an interval, and to the IP address, configured by the user. The mechanism then waits for a response within this interval. If no response is received before it times out, a second ping is sent and a response is expected within 10 seconds. If there is still no response, two more pings are sent at 5-second intervals. Finally, if there is still no response, the device reconnects to the network.

Note

As a result, you can verify that no reconnection has been recorded in the system logs if you wait long enough.

Step 4: Run command system journal clear at DUT0.

Step 5: Run command system journal show | cat at DUT0 and check if output does not contain the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 16 17:33:18.365581 osdx systemd-journald[158781]: Runtime Journal (/run/log/journal/59064056050347adb24af23311918fce) is 8.0M, max 80.3M, 72.3M free.
Apr 16 17:33:18.370455 osdx systemd-journald[158781]: Received client request to rotate journal, rotating.
Apr 16 17:33:18.370567 osdx systemd-journald[158781]: Vacuuming done, freed 0B of archived journals from /run/log/journal/59064056050347adb24af23311918fce.
Apr 16 17:33:18.447745 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal clear'.
Apr 16 17:33:22.827632 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Previous packet pending - ID: 14891, Sequence: 0
Apr 16 17:33:22.827647 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds

Note

However, when traffic control is applied, it is possible to prove the 'ping' command is failing because ICMP packets are being dropped.

Step 6: Run command system journal clear at DUT0.

Step 7: Modify the following configuration lines in DUT0 :

set interfaces cellular cell0 traffic control in PLOSS
set traffic control PLOSS type network-emulator packet-loss 100

Step 8: Expect a failure in the following command: Ping IP address 8.8.8.8 from DUT0:

admin@DUT0$ ping 8.8.8.8 count 1 size 56 timeout 1
Show output
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms

Note

You can verify that a reconnection has been recorded in the system logs if you wait long enough.

Step 9: Run command system journal show | cat at DUT0 and check if output contains the following tokens:

[Device/wwan0] Warning: [PDP#1] Requesting reconnection...
[Device/wwan0] Info: WDS[0]: Stopping network connection...
[Device/wwan0] Info: [PDP#1] Establishing network connection...
Show output
Apr 16 17:34:00.760954 osdx systemd-journald[158781]: Runtime Journal (/run/log/journal/59064056050347adb24af23311918fce) is 8.0M, max 80.3M, 72.3M free.
Apr 16 17:34:00.765826 osdx systemd-journald[158781]: Received client request to rotate journal, rotating.
Apr 16 17:34:00.765936 osdx systemd-journald[158781]: Vacuuming done, freed 0B of archived journals from /run/log/journal/59064056050347adb24af23311918fce.
Apr 16 17:34:00.835687 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal clear'.
Apr 16 17:34:01.010413 osdx OSDxCLI[199048]: User 'admin' entered the configuration menu.
Apr 16 17:34:01.121685 osdx OSDxCLI[199048]: User 'admin' added a new cfg line: 'set interfaces cellular cell0 traffic control in PLOSS'.
Apr 16 17:34:01.240611 osdx OSDxCLI[199048]: User 'admin' added a new cfg line: 'set traffic control PLOSS type network-emulator packet-loss 100'.
Apr 16 17:34:01.366706 osdx OSDxCLI[199048]: User 'admin' added a new cfg line: 'show changes'.
Apr 16 17:34:01.517293 osdx ubnt-cfgd[211598]: inactive
Apr 16 17:34:01.628754 osdx INFO[211608]: FRR daemons did not change
Apr 16 17:34:01.732899 osdx (udev-worker)[291]: ifb.cell0: Could not set Alias=, MACAddress=/MACAddressPolicy=, TransmitQueues=, ReceiveQueues=, TransmitQueueLength=, MTUBytes=, GenericSegmentOffloadMaxBytes= or GenericSegmentOffloadMaxSegments=, ignoring: Operation not supported
Apr 16 17:34:01.777305 osdx kernel: Mirror/redirect action on
Apr 16 17:34:01.791600 osdx cfgd[3872]: [199048]Completed change to active configuration
Apr 16 17:34:01.811641 osdx systemd[1]: osdx-ledsd.service: Sent signal SIGUSR2 to main process 4667 (osdx-ledsd) on client request.
Apr 16 17:34:01.811677 osdx osdx-ledsd[4667]: Config changed, checking config paths
Apr 16 17:34:01.814351 osdx OSDxCLI[199048]: User 'admin' committed the configuration.
Apr 16 17:34:01.853357 osdx OSDxCLI[199048]: User 'admin' left the configuration menu.
Apr 16 17:34:03.064235 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'ping 8.8.8.8 count 1 size 56 timeout 1'.
Apr 16 17:34:12.828385 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Previous packet pending - ID: 14891, Sequence: 5
Apr 16 17:34:12.828401 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 1 - interval reduced to 10 seconds
Apr 16 17:34:22.828569 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Previous packet pending - ID: 14891, Sequence: 6
Apr 16 17:34:22.828583 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 2 - interval reduced to 5 seconds
Apr 16 17:34:23.446243 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:24.830217 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:26.214230 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:27.602213 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:27.828753 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Previous packet pending - ID: 14891, Sequence: 7
Apr 16 17:34:27.828768 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 3 - interval reduced to 5 seconds
Apr 16 17:34:29.034228 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:30.566216 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:32.014223 osdx OSDxCLI[199048]: User 'admin' executed a new command: 'system journal show | cat'.
Apr 16 17:34:32.828941 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Previous packet pending - ID: 14891, Sequence: 8
Apr 16 17:34:32.828954 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Warning: Connection in failure - consecutive failures: 4 - interval reduced to 5 seconds
Apr 16 17:34:32.839396 osdx WARNING[211719]: [wwan0/1] Requesting reconnection...
Apr 16 17:34:32.845973 osdx wwan-cli-socket[211721]: [Device/wwan0] Info: wwan-cli-socket reconnect 60000 wwan0
Apr 16 17:34:32.846357 osdx wwan-module[4699]: [Device/wwan0] Info: Reconnecting device...
Apr 16 17:34:32.846369 osdx wwan-module[4699]: [Device/wwan0] Warning: [PDP#1] Requesting reconnection...
Apr 16 17:34:32.846426 osdx wwan-module[4699]: [Device/wwan0] Info: WDS[0]: Stopping network connection...
Apr 16 17:34:32.955268 osdx wwan-module[4699]: [Device/wwan0] Info: WDS[0]: Network connection was stopped!
Apr 16 17:34:32.961326 osdx kernel: net _wwan0: link_state 0x1 -> 0x0
Apr 16 17:34:32.963281 osdx wwan-module[4699]: [Device/wwan0] Info: Checking registration state...
Apr 16 17:34:32.983391 osdx wwan-accessibility-control[211499]: [Core/wwan0/1] Info: Execution stopped
Apr 16 17:34:32.983532 osdx systemd[1]: Stopping wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control...
Apr 16 17:34:32.985594 osdx systemd[1]: wwan-accessibility-control@wwan0pdp1.service: Deactivated successfully.
Apr 16 17:34:32.985975 osdx systemd[1]: Stopped wwan-accessibility-control@wwan0pdp1.service - WWAN Accessibility Control.
Apr 16 17:34:32.996516 osdx INFO[211725]: Stop DHCP client for cell0
Apr 16 17:34:33.003444 osdx dhclient[211732]: Killed old client process
Apr 16 17:34:33.019170 osdx wwan-module[4699]: [Device/wwan0] Info: Device registered and PS attached successfully
Apr 16 17:34:33.019186 osdx wwan-module[4699]: [Device/wwan0] Info: [PDP#1] Establishing network connection...
Apr 16 17:34:33.121571 osdx dhclient[211732]: DHCPRELEASE of 5.205.233.22 on cell0 to 5.205.233.21 port 67