Intermittent internet loss

frieza · 11-16-2015, 07:38 PM

I have been intermittently losing my internet connection recently, each time the modem loses it's IP address, and sometimes has to be rebooted, some times it re-connects on it's own

the modem is

Code:

Hardware Version 	DGN2200
Firmware Version 	V1.0.0.50_7.0.50
GUI Language Version 	V1.0.0.30

the service is AT&T standard DSL

i called tech support, for whatever good that did, and they told me they had 100 signal when they did the line test.

the most recent log

Code:

[DSL Event] DSL: Up Tuesday, Nov 17,2015 01:19:25
[Internet disconnected] Tuesday, Nov 17,2015 01:19:10
[DSL Event] DSL: Down Tuesday, Nov 17,2015 01:19:09
[DSL Event] DSL: Up Tuesday, Nov 17,2015 01:13:56
[Admin login] from source x.x.x.2, Tuesday, Nov 17,2015 01:13:33
[DOS Attack] : 1 [FIN Scan] packets detected in last 20 seconds, source ip [23.235.44.143]
 Tuesday, Nov 17,2015 01:01:20
[DOS Attack] : 1 [FIN Scan] packets detected in last 20 seconds, source ip [23.235.40.175]
 Tuesday, Nov 17,2015 01:01:16
[DOS Attack] : 1 [FIN Scan] packets detected in last 20 seconds, source ip [173.223.250.154]
 Tuesday, Nov 17,2015 00:59:07
[DOS Attack] : 1 [FIN Scan] packets detected in last 20 seconds, source ip [216.58.216.102]
 Tuesday, Nov 17,2015 00:55:23
[DOS Attack] : 1 [FIN Scan] packets detected in last 20 seconds, source ip [74.125.196.149]
 Tuesday, Nov 17,2015 00:55:21
[UPnP set event: Public_UPNP_C5] from source x.x.x.2, Tuesday, Nov 17,2015 00:54:46
[Internet connected] IP address: x.x5.147.188, Tuesday, Nov 17,2015 00:52:55
[DSL Event] DSL: Up Tuesday, Nov 17,2015 00:52:16
[Internet disconnected] Tuesday, Nov 17,2015 00:52:02
[DSL Event] DSL: Down Tuesday, Nov 17,2015 00:52:00
[Admin login] from source x.x.x.2, Tuesday, Nov 17,2015 00:33:22
[DHCP IP: (x.x.x.4)] to MAC address 8C:29:37:E5:D4:C6, Monday, Nov 16,2015 23:56:21
[DSL Event] DSL: Up Monday, Nov 16,2015 23:53:33
[DHCP IP: (x.x.x.4)] to MAC address 8C:29:37:E5:D4:C6, Monday, Nov 16,2015 23:24:56
[UPnP set event: Public_UPNP_C5] from source x.x.x.2, Monday, Nov 16,2015 23:19:13
[Internet connected] IP address: x.x9.120.85, Monday, Nov 16,2015 23:19:04
[DSL Event] DSL: Up Monday, Nov 16,2015 23:18:25
[Internet disconnected] Monday, Nov 16,2015 23:18:12
[DSL Event] DSL: Down Monday, Nov 16,2015 23:18:11
[DSL Event] DSL: Up Monday, Nov 16,2015 23:10:51
[UPnP set event: Public_UPNP_C5] from source x.x.x.2, Monday, Nov 16,2015 23:08:07
[Internet connected] IP address: x.x9.120.65, Monday, Nov 16,2015 23:06:01
[DSL Event] DSL: Up Monday, Nov 16,2015 23:05:24
[Internet disconnected] Monday, Nov 16,2015 23:05:08
[DSL Event] DSL: Down Monday, Nov 16,2015 23:05:08
[DHCP IP: (x.x.x.6)] to MAC address D8:E5:6D:7F:8E:6F, Monday, Nov 16,2015 23:02:09
[DSL Event] DSL: Up Monday, Nov 16,2015 22:59:38
[UPnP set event: Public_UPNP_C5] from source x.x.x.4, Monday, Nov 16,2015 22:58:24
[Admin login] from source x.x.x.2, Monday, Nov 16,2015 22:58:01
[DHCP IP: (x.x.x.10)] to MAC address 1C:6F:65:FE:7F:C1, Monday, Nov 16,2015 22:57:59
[DHCP IP: (x.x.x.5)] to MAC address 98:FC:11:AB:E2:24, Monday, Nov 16,2015 22:57:57
[Time synchronized with NTP server] Monday, Nov 16,2015 22:57:52
[UPnP set event: Public_UPNP_C5] from source x.x.x.2, Monday, Nov 16,2015 22:57:50
[DHCP IP: (x.x.x.10)] to MAC address 1C:6F:65:FE:7F:C1, Monday, Nov 16,2015 22:57:49
[UPnP set event: Public_UPNP_C5] from source x.x.x.2, Monday, Nov 16,2015 22:57:48
[DHCP IP: (x.x.x.4)] to MAC address 8C:29:37:E5:D4:C6, Monday, Nov 16,2015 22:57:43
[Internet connected] IP address: x.x.219.237, Monday, Nov 16,2015 22:57:42
[DSL Event] DSL: Up Monday, Nov 16,2015 22:57:39
[DHCP IP: (x.x.x.9)] to MAC address 58:3F:54:D9:34:D5, Monday, Nov 16,2015 22:57:38
[DHCP IP: (x.x.x.8)] to MAC address 80:71:7A:C0:E7:5D, Monday, Nov 16,2015 22:57:37
[Initialized, firmware version: V1.0.0.50_7.0.50] Monday, Nov 16,2015 22:57:21

connection statistics

Code:

+-----+----------+---------+-------+-----------+-------+-------+---------+
|Port |Status    |TxPkts   |RxPkts |Collisions |Tx B/s |Rx B/s |Up Time  |
+-----+----------+---------+-------+-----------+-------+-------+---------+
|WAN  |pppoe     |5693     |5450   |0          |999    |3267   |00:13:30 |
|LAN1 |Link Down |107504   |102346 |0          |9164   |1824   |--       |
|LAN2 |Link Down |--       |       |           |       |       |         |
|LAN3 |10M/100M  |02:36:22 |       |           |       |       |         |
|LAN4 |10M/100M  |02:36:22 |       |           |       |       |         |
|WLAN |145M      |40579    |43194  |0          |2432   |606    |02:35:57 |
+-----+----------+---------+-------+-----------+-------+-------+---------+
+-----------------+-----------+---------+
|ADSL Link        |Downstream |Upstream |
+-----------------+-----------+---------+
|Connection Speed |761 kbps   |380 kbps |
|Line Attenuation |53.0 db    |27.0 db  |
|Noise Margin     |31.7 db    |30.0 db  |
+-----------------+-----------+---------+

would you suspect a problem with the DSL line or the modem

edit:note, i've done some searching that suggests the fin scans might be orphaned packets due to an unstable connection rather than an actual attack.

frankbell · 11-16-2015, 08:06 PM

How old is that modem?

Assuming that the signal comes back immediately upon a reboot, I'd be inclined to suspect that it's not the line, but it might be worth a call to your ISP the next time it happens, before you reboot the modem. They can test the line before and after you reboot the modem.

I experienced similar symptoms several years ago (different ISP). Turns out that the modem was very old in modem years; I ended up replacing the modem and they went away.

frieza · 11-16-2015, 08:22 PM

Quote:

Originally Posted by frankbell

How old is that modem?

Assuming that the signal comes back immediately upon a reboot, I'd be inclined to suspect that it's not the line, but it might be worth a call to your ISP the next time it happens, before you reboot the modem. They can test the line before and after you reboot the modem.

I experienced similar symptoms several years ago (different ISP). Turns out that the modem was very old in modem years; I ended up replacing the modem and they went away.

that is a good question, and i id call them after it had dropped out, but prior to rebooting, but
1) it isn't one of the 'officially supported' modems (read: provided by them), so they can't do much about it, and
2) well, the customer support person didn't sound like they exactly knew what they were doing

frankbell · 11-16-2015, 09:12 PM

They should still be able to test the connection, regardless of the darn modem. My ISP did.

Heck, back when I was in Comcast territory, even Comcast was willing to test the line, even though I was using a third party modem. They wouldn't fix the modem, as it wasn't one of theirs, but they were willing to verify that their end of the connection was okay.

Then, again, no matter what name it trades under, AT&T is still Cingular, er, Southwestern Bell, the company that keeps changing its name for a reason.

You have my sympathies.

frieza · 11-16-2015, 09:17 PM

Quote:

Originally Posted by frankbell

They should still be able to test the connection, regardless of the darn modem. My ISP did.

Heck, back when I was in Comcast territory, even Comcast was willing to test the line, even though I was using a third party modem. They wouldn't fix the modem, as it wasn't one of theirs, but they were willing to verify that their end of the connection was okay.

Then, again, no matter what name it trades under, AT&T is still Cingular, er, Southwestern Bell, the company that keeps changing its name for a reason.

sorry, yes they said i had 100% signal strength, which was shortly after i had dropped off and auto reconnected without rebooting, most often the drop only lasts a few seconds, but it takes a moment to re-aquire an IP address and re-establish communication

frankbell · 11-16-2015, 09:23 PM

I think a new modem is probably indicated, but I'm not a tech on the spot, so that's just an educated guess. I think that the fact that rebooting the modem without changing anything else pretty much points the finger at the culprit.

Once you get one, you'll need to work with your ISP to get it "provisioned." (Why they call it "provisioning" I'll never know, but that's what they call it.)

I once had a problem that turned out to be the three-foot ethernet cable between the modem and the router, but, in that case, rebooting the modem did no good whatsoever. My ISP tech support person was really helpful in diagnosing that.

frieza · 11-16-2015, 09:25 PM

Quote:

Originally Posted by frankbell

I think a new modem is probably indicated, but I'm not a tech on the spot, so that's just an educated guess. I think that the fact that rebooting the modem without changing anything else pretty much points the finger at the culprit.

Once you get one, you'll need to work with your ISP to get it "provisioned." (Why they call it "provisioning" I'll never know, but that's what they call it.)

I once had a problem that turned out to be the three-foot ethernet cable between the modem and the router, but, in that case, rebooting the modem did no good whatsoever. My ISP tech support person was really helpful in diagnosing that.

hmm, mine is a pppoe so i think 'provisioning' simply means knowing the correct username/password to authenticate with the network but, thanks for the information.

frankbell · 11-16-2015, 10:07 PM

I've never had DSL. Sounds like if works sort of like augmented dialup.