Collab Network School Mesh Tests

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In these collaboration and networking tests, a School server equipped with one to three Active Antenna provides the interconnection for the laptops. In general, the laptops are registered with the school server and using the school's presence service.

Other networking modes tested are simple mesh, simple WiFi and school WiFi.

Startup & Registration

Startup is also frequently included in other tests, such as Chat (test 0323E), or Presence (test 0321D and test 0317E).

Test 0414A

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was a staged startup (2 every 5 sec) of 28 laptops. All had previously been registered with the school server. 28 out of the 28 had problems finding the school mesh portal! I suspect the Active Antenna/firmware/driver on the freshly rebooted school server

Twenty-eight laptops (X50 - X59, X62 - X79) were turned on sequentially, two laptops every five seconds. Each laptop had previously been registered with the school server.

17 of the laptops (X50 - X51, X53, X56 - X58, X63, X70, X73 - X74, and X79) did not find the school server mesh portal, and started a simple mesh instead (as in, but probably not, Trac 4153). Some of these may be falsely logged.

11 of the laptops (X52, X54, X55, X59, X62, X64 - X69, X71 - X72, X75 - X78) did not find the school mesh portal, but did not even join a simple mesh on failure (definitely Trac 5848).

The server ifconfig/iwconfig appeared normal. It was rebooted immediately before running this test. This behavior has been seen before, but only after weeks of operation...

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1, Chan 6, Chan 11

Laptop X69 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X74 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, /var/log/ejabberd, laptop list

Test 0414B

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was a staged startup (2 every 5 sec) of 28 laptops. All had previously been registered with the school server. 9 out of the 28 had problems finding the school mesh portal.

The school server was restarted at the beginning of this test.

Twenty-eight laptops (X50 - X59, X62 - X79) were turned on sequentially, two laptops every five seconds. Each laptop had previously been registered with the school server.

Four of the laptops (X53, X63, X73, and X78) did not find the school server mesh portal, and started a simple mesh instead (Trac 4153).

Five of the laptops (X62, X68, X72, X75, and X76) did not find the school mesh portal, but did not even join a simple mesh on failure (Trac 5848).

All failing laptops connected successfully with the school presence service simply by clicking on the appropriate mesh icon in the neighborhood view. Two of the laptops (X53 and X63) took two tries. X73 took a long time to show other laptops after reconnecting.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1, Chan 6, Chan 11

Laptop X62 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X63 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X73 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, /var/log/ejabberd, laptop list

Test 0414D

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was a staged startup (1 every 10 sec) of 28 laptops. All had previously been registered with the school server. 6 out of the 28 had problems finding the school mesh portal.

Twenty-eight laptops (X50 - X59, X62 - X79) were turned on sequentially, one laptops every ten seconds. Each laptop had previously been registered with the school server.

Two of the laptops (X51 and X73) did not find the school server mesh portal, and started a simple mesh instead (Trac 4153).

Four of the laptops (X59, X72, X76, and X77) did not find the school mesh portal, but did not even join a simple mesh on failure (Trac 5848).

All failing laptops connected successfully with the school presence service simply by clicking on the appropriate mesh icon in the neighborhood view. One of the laptops (X59) took two tries.

All laptops were connected to the school presence server, using gabble.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1, Chan 6, Chan 11

Server logs: /var/log/messages, /var/log/ejabberd, laptop list

Test 0410G

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was a staged startup of 28 laptops. All had previously been registered with the school server. 9 out of the 28 had problems finding the school mesh portal.

Twenty-eight laptops (X50 - X59, X62 - X79) were turned on sequentially, two laptops every five seconds. Each laptop had previously been registered with the school server.

Four of the laptops (X57, X70, X74, and X79) did not find the school server mesh portal, and started a simple mesh instead (Trac 4153).

Five of the laptops (X59, X68, X69, X71, and X77) did not find the school mesh portal, but did not even join a simple mesh on failure (Trac 5848).

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X70 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X77 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X79 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0410H

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was a staged startup of 28 laptops. All had previously been registered with the school server. 10 out of the 28 had problems finding the school mesh portal.

Twenty-eight laptops (X50 - X59, X62 - X79) were turned on sequentially, two laptops every five seconds. Each laptop had previously been registered with the school server.

Three of the laptops (X53, X57, and X73) did not find the school server mesh portal, and started a simple mesh instead (Trac 4153).

Seven of the laptops (X62, X64, X65, X66, X67, X72, and X76) did not find the school mesh portal, but did not even join a simple mesh on failure (Trac 5848).

No packet traces were obtained.

Laptop X53 logs: All, /var/log/messages, mesh routing tables, Telepathy/Sugar

Laptop X57 logs: All, /var/log/messages, mesh routing tables, Telepathy/Sugar

Laptop X73 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X76 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0323A

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous startup of 10 laptops, located on a single 0.7m x 1.5m table. 4 out of the 10 had problems finding the school mesh portal.

Ten laptops (X50 - X59) were turned on sequentially, with around one second between each startup. Each laptop had previously been registered with the school server. Four of the ten laptops (X51, X52, X57, X59) did not find the school server mesh portal, and started a simple mesh instead.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X59 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0323B

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous startup of 10 laptops, which were spatially dispersed around a 2m x 3m space. 2 out of the 10 had problems finding the school mesh portal.

Ten laptops (X51, X52, X57, X59, X69, X63, X71, X73, X76, X79) were turned on sequentially, with around one second between each startup. Each laptop had previously been registered with the school server. Two of the ten laptops (X52, X76) did not find the school server mesh portal, and started a simple mesh instead.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X52 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0323C

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous startup of 15 laptops, which were spatially evenly dispersed around a 2m x 3m space, with no laptops closer than 30 cm. to another unit in the test. 4 out of the 15 had problems finding the school mesh portal.

Fifteen laptops (X50, X52, X54, X56, X58, X62, X63, X65, X67, X69, X70, X72, X74, X77, X79) were turned on sequentially, with around one second between each startup. Each laptop had previously been registered with the school server. Four of the ten laptops (X54, X67, X69, X77) did not find the school server mesh portal, and started a simple mesh instead.

After the test was started, it was noticed that X57 (adjacent to X54 and X67) had been left sleeping instead of powered off, invalidating the even dispersion assumption of this test.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Server logs: /var/log/messages, laptop list

Test 0323D

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous startup of 10 laptops, which were spatially evenly dispersed around a 5m x 5m space, with no laptops closer than 60 cm. to another unit in the test. 4 out of the 10 had problems finding the school mesh portal.

Ten laptops (X52, X55, X59, X62, X64, X65, X69, X70, X76, X78) were turned on sequentially, with around two seconds between each startup. Each laptop had previously been registered with the school server. Four of the ten laptops (X65, X69, X70, X78) did not find the school server mesh portal, and started a simple mesh instead.

For this test, the table containing X60 - X69 was moved outside the room where it is shown in the test diagram. The school server antenna was located in the center of the space, about 1.5 m over the plane containing the laptops.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X70 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0323H

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a staggered startup of 20 laptops. 2 out of the 20 had problems finding the school mesh portal.

Twenty laptops (X50 - X59, X70 - X79) were turned on sequentially, two at a time with around 15 seconds between each pair. All laptops had previously been registered with the school server. Two of the twenty laptops (X70, X58) did not find the school server mesh portal, and started a simple mesh instead.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Server logs: /var/log/messages, laptop list

Test 0317D

Laptop Build: 699

School Server Build: 160

School Server Channels: 1

This test was a staged registration of 29 laptops. 7 out of the 29 had problems finding the school mesh portal. Once they found the portal, all of the laptops registered on the first try.

Ten laptops (X50 - X59) were turned on first. They all found the school server mesh portal. They were registered, the registration verified (on the Home Screen) and Sugar restarted using CTL-ALT-ERASE.

Another ten laptops (X61 - X70) were turned on. Four (X62, X64, X65, and X68) didn't find the school mesh portal, and joined a simple mesh on channel 1 (Trac 5963). Clicking on mesh channel 1 in the neighborhood view caused three of the laptops to find the school mesh portal, and trying twice worked on the fourth (X65).

Another nine laptops (X71 - X79) were turned on. Three of these didn't find the school mesh portal (Trac 4153), but all three found it on the first manual retry.

All of the laptop registered on the first try, but registration wasn't simultaneous.

Packet Traces: Chan 1, Chan 11, Chan 6

Test 0317C

Laptop Build: 699

School Server Build: 160

School Server Channels: 1

This test was supposed to be a staged registration of laptops. It was aborted after three (X52 - X54) of the first five laptops (X50 - X54) to be turned on couldn't find a school mesh portal and instead joined a simple mesh.

The school server active antenna had been placed on the same plane as the laptops (at 1 m from the floor). The antenna was moved to about 2 m off the floor, and the test repeated as 0317D.

Packet Traces: Chan 1, Chan 11, Chan 6

Presence

Test 0321D

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous booting up of 29 registered laptops and 9 unregistered ones. 15 out of the 38 had problems finding the school mesh portal (Trac 4153, 5963). Most found the mesh portal after the mesh 1 circle in the neighborhood view was clicked on, but three (X71, X92, X96) required a reboot. Once they found the portal, all of the unregistered laptops registered on the first try and all connected using gabble.

29 of the laptops (X50 - X59, X61 - X79) had previously been registered with the school server (and the school ejabberd server). They were upgraded to have telepathy-salut-0.2.3-1.olpc2.i386.rpm and all logs (libertas, telepathy, sugar) turned on. Another nine unregistered laptops (X90 - X98) were used without the upgraded telepathy-salut. Salut shouldn't be used when connected to a school server, so no difference was expected. They were all turned on within a ninety second period, starting with X50 and moving up.

23 of the 38 laptops found the school server mesh portal. The ones that didn't (Trac 4153, 5963) were X53, X54, X58, X59, X64, X71, X73, X74, X76, X77, X79, X91, X92, X95, and X96. Note less correlation with startup time than seen in Test 0317E.

Twelve of the failing laptops found the school mesh portal after clicking on mesh channel 1 in the neighborhood view. Three of the failing laptops (X71, X92, and X96) didn't find it after two clicks, but did find it immediately upon reboot.

Two of the laptops (X91 aka 00:17:C4:11:14:5D aka 172.18.10.236, and X92 aka 00:17:C4:0D:14:54 aka 172.18.11.234) entered a weird state after having Sugar rebooted to force an ejabberd registration after a registration of the laptop with the school server. Unfortunately, no logs were obtained and the problem disappeared on reboot. More details later...

Packet Traces: Chan 1, Chan 11, Chan 6

Laptop X59 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Laptop X71 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, output of school_who, laptop list

Discussion of Packet Traces

Test 0317E

Laptop Build: 699

School Server Build: 160

School Server Channels: 1

This test was a simultaneous booting up of 29 registered laptops. 8 out of the 29 had problems finding the school mesh portal (Trac 5963). Once they found the portal, all of the laptops connected using gabble (although three had to have sugar restarted before they would display neighbors properly.)

All 29 laptops (X50 - X59, X61 - X79) had previously been registered with the school server (and the school ejabberd server). They were turned on within a sixty second period, starting with X50 and moving up.

21 of the 29 laptops found the school server mesh portal. The ones that didn't (Trac 5963) were X57, X65, X68, X70, X72, X75, X78, and X79. Note that these were the last ones turned on!

All 8 failing laptops found the school mesh portal after clicking on mesh channel 1 in the neighborhood view. Three of the failing laptops (X65, X68, and X75) didn't show other laptops in their neighborhood view until Sugar was restarted. They were not running salut instead of gabble (they didn't show each other), instead they didn't show any other XOs at all.

Packet Traces: Chan 1, Chan 11, Chan 6

Server logs: /var/log/messages, later output of school_who

Discussion of Packet Traces

Chat

Test 0323E

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm + Chat 35

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a staggered startup of 15 laptops, which were spatially evenly dispersed around a 5m x 5m space, with no laptops closer than 20 cm. to another unit in the test. 2 out of the 15 had problems finding the school mesh portal. Then another 22 laptops were turned on slowly, and a chat session between nine of the thirty-seven laptops was tested. It worked fine.

Fifteen laptops (X50, X52, X54, X56, X58, X62, X63, X64, X65, X69, X70, X72, X74, X77, X79) were turned on sequentially, with around ten seconds between each startup. Each laptop had previously been registered with the school server. Two of the ten laptops (X56 and X58) did not find the school server mesh portal, and started a simple mesh instead.

The two failing laptops immediately joined the mesh when mesh channel 1 was clicked on in the neighborhood view. It took up to two minutes for the neighborhood view to reflect the newfound connection to a school server.

After a minute, another twenty-two laptops (others from X50 - X79 and X90 - X98) were turned on sequentially, with around ten seconds between each startup. Another four or five laptops failed to find the school mesh portal, but found it after restarting the network association process by clicking on mesh channel 1 in the neighborhood view.

Chat was started on laptop X65, and it was shared with the neighborhood.

In 60 sec, 31 laptops were showing the shared activity on their neighborhood view. The ones which didn't included X59, X63, X93, and X96). (Trac ticket ?, logs attached)

The Chat activity was joined sequentially, with around two seconds between join, by laptops X62, X64, X66 - X69, X54, and X74. All laptops successfully joined, and were able to type and have it seen by all other participants.

For this test, the table containing X60 - X69 was moved outside the room where it is shown in the test diagram. The school server antenna was located in the center of the space, about 1.5 m over the plane containing the laptops. The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X59 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Write Sharing

Test 0414C

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was 20 laptops sharing a write activity. All laptops saw the shared document, and were able to edit it. When all 20 were sharing the activity, the latency between typing and the update of remote laptops was significant (over a minute).

Twenty-eight laptops (X50 - X59, X62 - X79) were associated with a school server in a previous experiment. Any problems observed in that experiment were cleared up before starting this test.

A Write activity was started on laptop X69, and shared with the neighborhood. This was seen by all laptops.

Four laptops (X70 - X73) joined the activity, will full functionality.

Fifteen more laptops joined the activity, in three groups of five (X55 - X59, X50 - X54, and X64 - X68).

By the time the last group of five laptops joined the activity, the latency between typing and it being reflected on other laptops was significant. No data was really lost, although some laptops "lost sync" of the shared document, only to regain it a minute later.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1, Chan 6, Chan 11

Laptop X69 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, /var/log/ejabberd, laptop list

Test 0414E

Laptop Build: 703 + libertas firmware 22.p8

School Server Build: 160 + 22.p8 + Libertas drivers (4/9/08 HEAD of olpc-2.6 stable branch)

School Server Channels: 1

This test was 9 consecutive individual shares of a write activity between two laptops (using invites). 8 of the shares were succesful. In the ninth share, the laptop could not see the person he was to share with.

Twenty-eight laptops (X50 - X59, X62 - X79) were associated with a school server in a previous experiment. Any problems observed in that experiment were cleared up before starting this test. The school presence service was reporting 28 laptops online.

Write activities were started on laptops X50, X52, X54, X56, X58, X62, X64, X66, and X68. Each laptops invited the immediately adjacent laptop to share the activity. Thus, X50 invited X51, X52 invited X53, etc...

Laptop X58 could not see laptop X59. After checking, most laptops could not see X59, even though it was connected to the school presence service using gabble (ticket #6888).

All other shared activities were seen by the invited laptops. Joining the shared activities occurred without error. All laptops were able to modify and see modification on their shared document.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1, Chan 6, Chan 11

Laptop X58 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X59 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, /var/log/ejabberd, laptop list

Test 0321E

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm + Write 55

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test started with 37 students connected to a school server (subsequent to test 0321D). All were registered with the server and using Telepathy-Gabble. All students could see one another in their neighborhood views.

Started Write activity on X69 aka 00:17:c4:0d:00:01 aka 172.18.10.248. Shared the activity with the neighborhood. It was seen by all students.

The activity was successfully joined by five students (X70 - X74).

Started another Write activity on X58. Shared the activity with the neighborhood. It was seen by all students.

This second activity was successfully joined by five students (X61 - X65).

Characters were typed by X69 through X74, they were all seen by all activity participants.

Typed on X61 and crashed write. The first character typed was successfully sent to all laptops. I was frustratingly unable to get the logs as the keyboard had a stuck CTL key !!!

Packet Traces: Chan 1, Chan 11, Chan 6

Read Sharing

Test 0323F

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm + Read 44

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a simultaneous startup of 10 laptops, which were located on a 0.7m x 1.5m table. 2 out of the 10 had problems finding the school mesh portal. All were successfully registered, then a read activity was successfully shared to all laptops.

Ten laptops (X20 - X29) were turned on sequentially, with around one seconds between each startup. None of the laptops had previously been registered with the school server. Two of the ten laptops (X27 and X28) did not find the school server mesh portal, and started a simple mesh instead.

X20 - X26 and X29 were registered with the school server (all within a second), and Sugar was restarted.

X27 and X28 associated immediately with the school mesh portal when mesh channel 1 was clicked on. They too registered immediately and had Sugar restarted.

All laptops saw all other laptops in their neighborhood view.

A PDF document (VGA Pinout, about 40 KB), stored on laptop X25, was opened using Read. The activity was shared with the neighborhood. The shared activity was seen by all laptops.

The shared Read activity was joined by X26, and worked! X27, X28, and X29 then joined within a couple of seconds of each other. They too were successful (although it took around a minute for X29 to load the document). Finally, laptops X20 - X24 joined. All successfully loaded the shared document.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Server logs: /var/log/messages, laptop list

Test 0323G

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm + Read 44

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: 1

This test was a staggered startup of 10 laptops, which were located on a 0.7m x 1.5m table. 1 out of the 10 had problems finding the school mesh portal. A read activity was successfully shared to all laptops.

Ten laptops (X20 - X29) were turned on sequentially, with around five seconds between each startup. All of the laptops had previously been registered with the school server. One of the ten laptops (X28) did not find the school server mesh portal, and started a simple mesh instead.

X28 associated immediately with the school mesh portal when mesh channel 1 was clicked on.

All laptops saw all other laptops in their neighborhood view.

A PDF document (VGA Pinout, about 40 KB), stored on laptop X24, was opened using Read. The activity was shared with the neighborhood. The shared activity was seen by all laptops.

The shared Read activity was joined by laptops X20 - X23 and X25 - X29, with two or three seconds between joins. All successfully loaded the shared document.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1 (a), Chan 1 (b), Chan 1 (c)

Server logs: /var/log/messages, laptop list