Доброго времени суток. Я пользуюсь роутером D-Link DSL-2520u/bru/d, ревизия D1, версия прошивки RU_1.20 (ftp.dlink.ru/pub/ADSL/DSL-2520U_BRU_D/Firmware/RU_1.20).
Суть проблемы в том,что время от времени пропадает интернет. Лампочка "интернет" на устройстве краснеет, а через некоторое время меняет свой цвет на зеленый. В это время интернет восстанавливается. На последующих прошивках (RU_1.30, RU_1.31, RU_1.32) соединение автоматически не восстанавливается вообще,а только при повторном включении роутера,но опять же не надолго. Если идет закачка файлов не через P2P клиент, а через браузер, то закачка останавливается. После разрыва интернета приходиться возобновлять её вручную. Это приносит некоторые неудобства, так как за компьютером нахожусь не постоянно.Интернет нужен круглосуточно.

Провайдер Центртелеком, режим модуляции на DSLAM и на роутере ADSL2+.

Statistics -- ADSL
Mode: ADSL2+
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 14.9 10.2
Attenuation (dB): 29.5 9.5
Output Power (dBm): 12.6 19.8
Attainable Rate (Kbps): 18928 1261
Rate (Kbps): 16053 1244
MSGc (number of bytes in overhead channel message): 115 11
B (number of bytes in Mux Data Frame): 246 13
M (number of Mux Data Frames in FEC Data Frame): 1 16
T (Mux Data Frames over sync bytes): 1 10
R (number of check bytes in FEC Data Frame): 8 8
S (ratio of FEC over PMD Data Frame length): 0.5304 6.1867
L (number of bits in PMD Data Frame): 3846 300
D (interleaver depth): 64 8
Delay (msec): 8 12

Super Frames: 623169 624821
Super Frame Errors: 64 5416
RS Words: 75403452 2163185
RS Correctable Errors: 14662 45884
RS Uncorrectable Errors: 1273 N/A

HEC Errors: 52 48703
OCD Errors: 0 0
LCD Errors: 0 0
Total Cells: 378524808 3753070983
Data Cells: 2639127 557638205
Bit Errors: 0 4155360

Total ES: 47 1655
Total SES: 0 424
Total UAS: 36 1966611



Лог устройства в момент разрыва:

--------------------

Date/Time Facility Severity Message
Jan 1 00:00:31 user crit kernel: ADSL G.992 message exchange
Jan 1 00:00:32 user crit kernel: ADSL link down
Jan 1 00:00:33 user crit kernel: eth0 Link DOWN.
Jan 1 00:00:33 user crit kernel: ADSL G.994 training
Jan 1 00:00:33 user info kernel: br0: port 2(eth0) entering disabled state
Jan 1 00:00:34 user crit kernel: eth0 Link UP.
Jan 1 00:00:35 user info kernel: br0: port 2(eth0) entering learning state
Jan 1 00:00:35 user info kernel: br0: topology change detected, propagating
Jan 1 00:00:35 user info kernel: br0: port 2(eth0) entering forwarding state
Jan 1 00:00:41 user crit kernel: ADSL G.992 started
Jan 1 00:00:46 user crit kernel: ADSL G.992 channel analysis
Jan 1 00:00:52 user crit kernel: ADSL G.992 message exchange
Jan 1 00:00:53 user crit kernel: ADSL link up, interleaved, us=1211, ds=10672
Jan 1 00:00:53 user warn kernel: ATM Soft SAR: ATM link connected.
Jan 1 00:00:54 user debug syslog: iptables -t nat -A PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 128.9.0.107
Jan 1 00:00:55 daemon info pppd[302]: PPP session is 40635
Jan 1 00:00:55 daemon info pppd[302]: Using interface ppp0_10_40_1
Jan 1 00:00:55 daemon notice pppd[302]: Connect: ppp_0_10_40_1 <--> nas_0_10_40
Jan 1 00:00:55 daemon warn pppd[302]: Couldn't increase MRU to 1500
Jan 1 00:00:57 daemon info pppd[302]: CHAP authentication succeeded
Jan 1 00:00:57 daemon notice pppd[302]: peer from calling number 00:15:FA:4F:C5:3C authorized
Jan 1 00:00:57 daemon notice pppd[302]: local IP address 77.45.227.174
Jan 1 00:00:57 daemon notice pppd[302]: remote IP address 80.82.53.124
Jan 1 00:00:57 daemon notice pppd[302]: primary DNS address 80.82.32.9
Jan 1 00:00:57 daemon notice pppd[302]: secondary DNS address 80.82.33.65
Jan 1 00:00:58 user debug syslog: route add default gw 80.82.53.124 2>/dev/null
Jan 1 00:00:58 user debug syslog: iptables -A FORWARD -o ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:58 user debug syslog: iptables -A FORWARD -i ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:58 user debug syslog: echo > /proc/net/ip_conntrack
Jan 1 00:00:58 user debug syslog: echo "1000" > /proc/sys/net/ipv4/ip_conntrack_max
Jan 1 00:00:58 user debug syslog: iptables -t nat -D PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 128.9.0.107 2>/dev/null
Jan 1 00:00:58 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Jan 1 00:00:58 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE
Jan 1 00:00:58 user debug syslog: iptables -t nat -D PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 80.82.32.9 2>/dev/null
Jan 1 00:00:58 user debug syslog: iptables -t nat -A PREROUTING -i br0 -d 192.168.1.1 -p udp --dport 53 -j DNAT --to 80.82.32.9
Jan 1 00:00:58 user debug syslog: /bin/dnsprobe &
Jan 1 00:00:59 user debug syslog: kill -9 300
Jan 1 00:00:59 user notice dnsprobe[945]: dnsprobe started!
Jan 1 00:00:59 user debug syslog: echo > /var/hosts
Oct 27 16:13:44 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=85.118.226.182 DST=77.45.227.174 LEN=60 TOS=0x00 PREC=0x00 TTL=53 ID=64935 DF PROTO=TCP SPT=35897 DPT=61059 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 16:13:47 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=85.118.226.182 DST=77.45.227.174 LEN=60 TOS=0x00 PREC=0x00 TTL=53 ID=64936 DF PROTO=TCP SPT=35897 DPT=61059 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 16:13:53 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=85.118.226.182 DST=77.45.227.174 LEN=60 TOS=0x00 PREC=0x00 TTL=53 ID=64937 DF PROTO=TCP SPT=35897 DPT=61059 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 16:14:04 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=93.185.176.157 DST=77.45.227.174 LEN=64 TOS=0x00 PREC=0x00 TTL=52 ID=1833 DF PROTO=TCP SPT=61105 DPT=23867 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 16:14:05 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=93.185.176.157 DST=77.45.227.174 LEN=64 TOS=0x00 PREC=0x00 TTL=52 ID=2166 DF PROTO=TCP SPT=61105 DPT=23867 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 16:32:01 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=77.45.198.163 DST=77.45.227.174 LEN=60 TOS=0x00 PREC=0x00 TTL=62 ID=28733 DF PROTO=TCP SPT=10376 DPT=32459 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 16:37:23 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=77.45.152.120 DST=77.45.227.174 LEN=48 TOS=0x00 PREC=0x00 TTL=123 ID=10191 DF PROTO=TCP SPT=26853 DPT=32459 WINDOW=8192 RES=0x00 SYN URGP=0
Oct 27 16:42:19 user warn kernel: AdslCoreEcUpdTmr: timeMs=1800170 ecUpdMask=0x40000
Oct 27 16:44:21 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.79.195.173 DST=77.45.227.174 LEN=60 TOS=0x00 PREC=0x00 TTL=55 ID=1183 DF PROTO=TCP SPT=3266 DPT=32459 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 16:51:24 daemon info pppd[302]: No response to 3 echo-requests
Oct 27 16:51:24 daemon notice pppd[302]: Serial link appears to be disconnected.
Oct 27 16:51:24 daemon info pppd[302]: Connect time 5166290.5 minutes.
Oct 27 16:51:24 daemon info pppd[302]: Sent 128443613 bytes, received 5468876 bytes.
Oct 27 16:51:24 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 16:51:30 daemon notice pppd[302]: Connection terminated....
Oct 27 16:51:33 daemon info pppd[302]: Sent PADT
Oct 27 16:51:38 daemon info pppd[302]: Sent PADT
Oct 27 16:51:38 daemon info pppd[302]: PPP session is 51682
Oct 27 16:51:38 daemon info pppd[302]: Using interface ppp0_10_40_1
Oct 27 16:51:38 daemon notice pppd[302]: Connect: ppp_0_10_40_1 <--> nas_0_10_40
Oct 27 16:51:38 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 16:51:41 daemon info pppd[302]: CHAP authentication succeeded
Oct 27 16:51:41 daemon notice pppd[302]: peer from calling number 00:15:FA:1C:B7:3C authorized
Oct 27 16:51:41 daemon notice pppd[302]: local IP address 77.45.174.81
Oct 27 16:51:41 daemon notice pppd[302]: remote IP address 80.82.53.125
Oct 27 16:51:41 daemon notice pppd[302]: primary DNS address 80.82.32.9
Oct 27 16:51:41 daemon notice pppd[302]: secondary DNS address 80.82.33.65
Oct 27 16:51:41 user debug syslog: route add default gw 80.82.53.125 2>/dev/null
Oct 27 16:51:41 user debug syslog: iptables -A FORWARD -o ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 16:51:41 user debug syslog: iptables -A FORWARD -i ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 16:51:41 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Oct 27 16:51:41 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE
Oct 27 16:57:24 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=18084 DF PROTO=TCP SPT=3273 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 16:57:27 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=18822 DF PROTO=TCP SPT=3273 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 16:57:33 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=20339 DF PROTO=TCP SPT=3273 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:05:22 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=82.207.115.132 DST=77.45.174.81 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=42728 DF PROTO=TCP SPT=35850 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 17:05:25 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=82.207.115.132 DST=77.45.174.81 LEN=60 TOS=0x00 PREC=0x00 TTL=50 ID=42729 DF PROTO=TCP SPT=35850 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0
Oct 27 17:08:10 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=11535 DF PROTO=TCP SPT=2910 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:12:35 syslog info -- MARK --
Oct 27 17:21:10 daemon info pppd[302]: No response to 3 echo-requests
Oct 27 17:21:10 daemon notice pppd[302]: Serial link appears to be disconnected.
Oct 27 17:21:10 daemon info pppd[302]: Connect time 29.5 minutes.
Oct 27 17:21:10 daemon info pppd[302]: Sent 74159825 bytes, received 39779760 bytes.
Oct 27 17:21:11 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 17:21:17 daemon notice pppd[302]: Connection terminated....
Oct 27 17:21:20 daemon info pppd[302]: Sent PADT
Oct 27 17:21:20 daemon info pppd[302]: PPP session is 11474
Oct 27 17:21:20 daemon info pppd[302]: Using interface ppp0_10_40_1
Oct 27 17:21:20 daemon notice pppd[302]: Connect: ppp_0_10_40_1 <--> nas_0_10_40
Oct 27 17:21:20 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 17:21:22 daemon info pppd[302]: CHAP authentication succeeded
Oct 27 17:21:22 daemon notice pppd[302]: peer from calling number 00:15:FA:1C:B7:3C authorized
Oct 27 17:21:22 daemon notice pppd[302]: local IP address 77.45.174.81
Oct 27 17:21:22 daemon notice pppd[302]: remote IP address 80.82.53.125
Oct 27 17:21:22 daemon notice pppd[302]: primary DNS address 80.82.32.9
Oct 27 17:21:22 daemon notice pppd[302]: secondary DNS address 80.82.33.65
Oct 27 17:21:23 user debug syslog: route add default gw 80.82.53.125 2>/dev/null
Oct 27 17:21:23 user debug syslog: iptables -A FORWARD -o ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 17:21:23 user debug syslog: iptables -A FORWARD -i ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 17:21:23 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Oct 27 17:21:23 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE
Oct 27 17:21:27 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=77.45.207.20 DST=77.45.174.81 LEN=52 TOS=0x00 PREC=0x00 TTL=123 ID=12011 DF PROTO=TCP SPT=10462 DPT=44444 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:24:14 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=59489 DF PROTO=TCP SPT=3722 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:24:23 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=80.82.51.234 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=61363 DF PROTO=TCP SPT=3722 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:26:59 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.33.220 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=12423 DF PROTO=TCP SPT=29478 DPT=32459 WINDOW=16384 RES=0x00 SYN URGP=0
Oct 27 17:27:02 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.33.220 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=124 ID=12684 DF PROTO=TCP SPT=29478 DPT=32459 WINDOW=16384 RES=0x00 SYN URGP=0
Oct 27 17:38:32 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=77.45.208.113 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=123 ID=33945 DF PROTO=TCP SPT=2060 DPT=8888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:43:13 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=77.45.213.18 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=123 ID=17009 DF PROTO=TCP SPT=11192 DPT=36888 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:51:33 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=70.107.128.246 DST=77.45.174.81 LEN=48 TOS=0x00 PREC=0x00 TTL=46 ID=316 DF PROTO=TCP SPT=57314 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0
Oct 27 17:59:22 daemon info pppd[302]: No response to 3 echo-requests
Oct 27 17:59:22 daemon notice pppd[302]: Serial link appears to be disconnected.
Oct 27 17:59:22 daemon info pppd[302]: Connect time 38.0 minutes.
Oct 27 17:59:22 daemon info pppd[302]: Sent 256839763 bytes, received 32710053 bytes.
Oct 27 17:59:22 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 17:59:28 daemon notice pppd[302]: Connection terminated....
Oct 27 17:59:31 daemon info pppd[302]: Sent PADT
Oct 27 17:59:31 daemon info pppd[302]: PPP session is 8166
Oct 27 17:59:31 daemon info pppd[302]: Using interface ppp0_10_40_1
Oct 27 17:59:31 daemon notice pppd[302]: Connect: ppp_0_10_40_1 <--> nas_0_10_40
Oct 27 17:59:31 daemon warn pppd[302]: Couldn't increase MRU to 1500
Oct 27 17:59:33 daemon info pppd[302]: CHAP authentication succeeded
Oct 27 17:59:33 daemon notice pppd[302]: peer from calling number 00:15:FA:4F:C5:3C authorized
Oct 27 17:59:34 daemon notice pppd[302]: local IP address 77.45.217.110
Oct 27 17:59:34 daemon notice pppd[302]: remote IP address 80.82.53.124
Oct 27 17:59:34 daemon notice pppd[302]: primary DNS address 80.82.32.9
Oct 27 17:59:34 daemon notice pppd[302]: secondary DNS address 80.82.33.65
Oct 27 17:59:34 user debug syslog: route add default gw 80.82.53.124 2>/dev/null
Oct 27 17:59:34 user debug syslog: iptables -A FORWARD -o ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 17:59:34 user debug syslog: iptables -A FORWARD -i ppp_0_10_40_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Oct 27 17:59:34 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Oct 27 17:59:34 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_10_40_1 -s 192.168.1.0/255.255.255.0 -j MASQUERADE
Oct 27 17:59:37 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.20.104 DST=77.45.217.110 LEN=48 TOS=0x00 PREC=0x00 TTL=126 ID=23256 DF PROTO=TCP SPT=62150 DPT=48631 WINDOW=8192 RES=0x00 SYN URGP=0
Oct 27 17:59:37 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.20.104 DST=77.45.217.110 LEN=48 TOS=0x00 PREC=0x00 TTL=126 ID=23257 DF PROTO=TCP SPT=54467 DPT=48631 WINDOW=8192 RES=0x00 SYN URGP=0
Oct 27 17:59:40 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.20.104 DST=77.45.217.110 LEN=48 TOS=0x00 PREC=0x00 TTL=126 ID=23686 DF PROTO=TCP SPT=62150 DPT=48631 WINDOW=8192 RES=0x00 SYN URGP=0
Oct 27 17:59:40 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.20.104 DST=77.45.217.110 LEN=48 TOS=0x00 PREC=0x00 TTL=126 ID=23687 DF PROTO=TCP SPT=54467 DPT=48631 WINDOW=8192 RES=0x00 SYN URGP=0
Oct 27 17:59:46 user alert kernel: Intrusion -> IN=ppp_0_10_40_1 OUT= MAC= SRC=95.32.20.104 DST=77.45.217.110 LEN=48 TOS=0x00 PREC=0x00 TTL=126 ID=24597 DF PROTO=TCP SPT=62150 DPT=48631 WINDOW=8192 RES=0x00 SYN URGP=0
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Вопросы:
1.Как прекратить разрывы интернета?
2.Кто виноват провайдер или я?

Хотелось бы услышать мнение техподдержки по озвученной проблеме. Готов предоставить дополнительную информацию для локализации проблемы с целью её устранения.

Проблема решена включением опции "Bridge PPPoE Frames Between WAN and Local Ports" на прошивке RU_1.32. Сутки работы-ни одного дисконнекта.
Всем спасибо за помощь.