Являюсь абонентом провайдера Optima Telecom (Украина). Недавно сменил тарифный план, вместе с этим сменил модем - отдал провайдеру выданный в оренду 2500U без BRU и прикупил себе 2520U/BRU. И тут начались чудеса, интернет начал тупить, в режиме роутера иногда может не подключится (в логах Remote message: incorrect login и так несколько раз потом в конце exit - помогает перезапуск модема), в логах модема частые записи dns query failed (иногда помогает только перезапуск модема). Думаю может проблема в модеме. Взял на пробу 2500U/BRU. Ситуация не изменилась. Может объясните в чем проблема на стороне прова или в модеме что не так. На старом модеме таких проблем небыло. Кстати попутный вопрос - на 2500U/BRU индикатор status мигает все время с одинаковым промежутком времени, а на 2520U/BRU время от времени помигивает (промежутки времени между миганиями разные) -это нормально?
И еще в момент активности (открытия страниц или закачки) на 2500U/BRU мигает DSL, STATUS и LAN, на 2520 в момент активности только STATUS и LAN - так и должно быть? Спасибо за ответ!

Это нормально.
Приведите вывод страницы Device Info > Statistics > ADSL. Укажите версию прошивки модема.

Statistics -- ADSL

Mode: G.DMT
Type: Interleave
Line Coding: Trellis On
Status: No Defect
Link Power State: L0

Downstream Upstream
SNR Margin (dB): 29.1 20.0
Attenuation (dB): 13.0 8.5
Output Power (dBm): 12.4 16.9
Attainable Rate (Kbps): 12064 1372
Rate (Kbps): 6144 768
K (number of bytes in DMT frame): 193 25
R (number of check bytes in RS code word): 0 4
S (RS code word size in DMT frame): 1 4
D (interleaver depth): 16 4
Delay (msec): 4 4

Super Frames: 1922809 1922829
Super Frame Errors: 1 0
RS Words: 0 32686087
RS Correctable Errors: 0 0
RS Uncorrectable Errors: 0 N/A

HEC Errors: 1 0
OCD Errors: 0 0
LCD Errors: 0 0
Total Cells: 473664536 0
Data Cells: 209023 0
Bit Errors: 0 0

Total ES: 1 0
Total SES: 0 0
Total UAS: 12 0

А а вот лог
System Log

Date/Time Facility Severity Message
Jan 1 00:00:14 user warn kernel: brcmboard: brcm_board_init entry
Jan 1 00:00:14 user warn kernel:
Jan 1 00:00:14 user warn kernel: ======= GPIO CONFIG_BCM96338 inited ========
Jan 1 00:00:14 user info kernel: Serial: BCM63XX driver $Revision: 3.00 $
Jan 1 00:00:14 user warn kernel: ttyS0 at MMIO 0xfffe0300 (irq = 10) is a BCM63XX
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 2
Jan 1 00:00:14 user info kernel: IP: routing cache hash table of 512 buckets, 4Kbytes
Jan 1 00:00:14 user info kernel: TCP: Hash tables configured (established 512 bind 1024)
Jan 1 00:00:14 user warn kernel: ip_conntrack version 2.1 (125 buckets, 0 max) - 376 bytes per conntrack
Jan 1 00:00:14 user warn kernel: ip_tables: (C) 2000-2002 Netfilter core team
Jan 1 00:00:14 user info kernel: Initializing IPsec netlink socket
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 1
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 17
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 15
Jan 1 00:00:14 user notice kernel: Ebtables v2.0 registered
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 8
Jan 1 00:00:14 user info kernel: NET: Registered protocol family 20
Jan 1 00:00:14 user info kernel: 802.1Q VLAN Support v1.8 Ben Greear
Jan 1 00:00:14 user info kernel: All bugs added by David S. Miller
Jan 1 00:00:14 user warn kernel: VFS: Mounted root (squashfs filesystem) readonly.
Jan 1 00:00:14 user info kernel: Freeing unused kernel memory: 76k freed
Jan 1 00:00:14 user warn kernel: Algorithmics/MIPS FPU Emulator v1.5
Jan 1 00:00:14 user warn kernel: atmapi: module license 'Proprietary' taints kernel.
Jan 1 00:00:14 user warn kernel: adsl: adsl_init entry
Jan 1 00:00:14 user warn kernel: blaadd: blaa_detect entry
Jan 1 00:00:14 user info kernel: Broadcom BCMPROCFS v1.0 initialized
Jan 1 00:00:14 user warn kernel: Broadcom BCM6338A2 Ethernet Network Device v0.3 Nov 21 2007 19:12:30
Jan 1 00:00:14 user warn kernel: Config Internal PHY Through MDIO
Jan 1 00:00:14 user info kernel: BCM63xx_ENET: 100 MB Full-Duplex (auto-neg)
Jan 1 00:00:14 user warn kernel: eth0: MAC Address: 00:1C:F0:28:B8:65
Jan 1 00:00:14 user warn kernel: Broadcom BCM6338A2 USB Network Device v0.4 Nov 21 2007 19:12:32
Jan 1 00:00:14 user warn kernel: usb0: MAC Address: 00 1C F0 28 B8 66
Jan 1 00:00:14 user warn kernel: usb0: Host MAC Address: 00 1C F0 28 B8 67
Jan 1 00:00:14 user crit kernel: eth0 Link UP.
Jan 1 00:00:14 user warn kernel: BcmAdsl_Initialize=0xC00733F8, g_pFnNotifyCallback=0xC008BC64
Jan 1 00:00:14 user warn kernel: AnnexCParam=0x7FFF7EB8 AnnexAParam=0x00000980 adsl2=0x00000000
Jan 1 00:00:14 user warn kernel: pSdramPHY=0xA0FFFFF8, 0x0 0x0
Jan 1 00:00:14 user warn kernel: AdslCoreHwReset: AdslOemDataAddr = 0xA0FFD3D4
Jan 1 00:00:14 user warn kernel: AnnexCParam=0x7FFF7EB8 AnnexAParam=0x00000980 adsl2=0x00000000
Jan 1 00:00:14 user warn kernel: dgasp: kerSysRegisterDyingGaspHandler: dsl0 registered
Jan 1 00:00:14 user warn kernel: ATM proc init !!!
Jan 1 00:00:14 user warn kernel: ip_conntrack_pptp version 2.1 loaded
Jan 1 00:00:14 user warn kernel: ip_nat_pptp version 2.0 loaded
Jan 1 00:00:14 user crit kernel: ADSL G.994 training
Jan 1 00:00:14 user info kernel: device usb0 entered promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 1(usb0) entering learning state
Jan 1 00:00:14 user info kernel: br0: topology change detected, propagating
Jan 1 00:00:14 user info kernel: br0: port 1(usb0) entering forwarding state
Jan 1 00:00:14 user info kernel: device eth0 entered promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 2(eth0) entering learning state
Jan 1 00:00:14 user info kernel: br0: topology change detected, propagating
Jan 1 00:00:14 user info kernel: br0: port 2(eth0) entering forwarding state
Jan 1 00:00:14 user info kernel: device usb0 left promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 1(usb0) entering disabled state
Jan 1 00:00:14 user info kernel: device eth0 left promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 2(eth0) entering disabled state
Jan 1 00:00:14 user emerg kernel: 6>device usb0 entered promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 1(usb0) entering learning state
Jan 1 00:00:14 user info kernel: br0: topology change detected, propagating
Jan 1 00:00:14 user info kernel: br0: port 1(usb0) entering forwarding state
Jan 1 00:00:14 user info kernel: device eth0 entered promiscuous mode
Jan 1 00:00:14 user info kernel: br0: port 2(eth0) entering learning state
Jan 1 00:00:14 user info kernel: br0: topology change detected, propagating
Jan 1 00:00:14 user info kernel: br0: port 2(eth0) entering forwarding state
Jan 1 00:00:14 user debug syslog: echo > /var/snmpd.conf
Jan 1 00:00:14 user crit kernel: ADSL G.992 started
Jan 1 00:00:15 user debug syslog: echo > /var/hosts
Jan 1 00:00:15 user warn kernel:
Jan 1 00:00:15 user warn kernel: ioctl, p_name=diapd
Jan 1 00:00:15 user debug syslog: pppd plugin pppoe rp_pppoe_service Optima nas_0_0_33 nodetach user 'abramyak' password ************* interface_name 0_0_33_1 usepeerdns refuse-eap persist lcp-echo-interval 30 holdoff 3 nomppc nomppe mtu 14
Jan 1 00:00:16 daemon info pppd[282]: RP-PPPoE plugin version 3.3 compiled against pppd 2.4.3
Jan 1 00:00:16 daemon info pppd[282]: Plugin pppoe called.
Jan 1 00:00:16 daemon notice pppd[282]: pppd 2.4.3 started by admin, uid 0
Jan 1 00:00:16 user info kernel: br0: port 1(usb0) entering disabled state
Jan 1 00:00:16 user crit kernel: ADSL G.992 channel analysis
Jan 1 00:00:21 user crit kernel: ADSL G.992 message exchange
Jan 1 00:00:21 user crit kernel: ADSL link up, interleaved, us=768, ds=6144
Jan 1 00:00:21 user warn kernel: ATM Soft SAR: ATM link connected.
Jan 1 00:00:23 user debug syslog: iptables -t nat -A PREROUTING -i br0 -d 192.168.0.254 -p udp --dport 53 -j DNAT --to 128.9.0.107
Jan 1 00:00:28 daemon info pppd[282]: PPP session is 51075
Jan 1 00:00:28 daemon info pppd[282]: Using interface ppp0_0_33_1
Jan 1 00:00:28 daemon notice pppd[282]: Connect: ppp_0_0_33_1 <--> nas_0_0_33
Jan 1 00:00:28 daemon warn pppd[282]: Couldn't increase MRU to 1500
Jan 1 00:00:30 daemon warn pppd[282]: Couldn't increase MRU to 1500
Jan 1 00:00:30 daemon info pppd[282]: Remote message: Welcome
Jan 1 00:00:30 daemon notice pppd[282]: PAP authentication succeeded
Jan 1 00:00:30 daemon notice pppd[282]: peer from calling number 00:11:2F:0C:DD:6B authorized
Jan 1 00:00:30 daemon notice pppd[282]: local IP address 212.86.253.193
Jan 1 00:00:30 daemon notice pppd[282]: remote IP address 212.86.252.100
Jan 1 00:00:30 daemon notice pppd[282]: primary DNS address 213.227.192.130
Jan 1 00:00:30 daemon notice pppd[282]: secondary DNS address 195.248.191.72
Jan 1 00:00:31 user debug syslog: route add default gw 212.86.252.100 2>/dev/null
Jan 1 00:00:31 user debug syslog: iptables -A FORWARD -o ppp_0_0_33_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:31 user debug syslog: iptables -A FORWARD -i ppp_0_0_33_1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
Jan 1 00:00:31 user debug syslog: echo > /proc/net/ip_conntrack
Jan 1 00:00:31 user debug syslog: echo "1000" > /proc/sys/net/ipv4/ip_conntrack_max
Jan 1 00:00:31 user debug syslog: iptables -t nat -D PREROUTING -i br0 -d 192.168.0.254 -p udp --dport 53 -j DNAT --to 128.9.0.107 2>/dev/null
Jan 1 00:00:31 user debug syslog: iptables -t nat -D POSTROUTING -o ppp_0_0_33_1 -s 192.168.0.0/255.255.255.0 -j MASQUERADE 2>/dev/null
Jan 1 00:00:31 user debug syslog: iptables -t nat -A POSTROUTING -o ppp_0_0_33_1 -s 192.168.0.0/255.255.255.0 -j MASQUERADE
Jan 1 00:00:31 user debug syslog: kill -9 276
Jan 1 00:00:31 user debug syslog: echo > /var/hosts
May 14 03:57:33 user warn syslog: dns query failed
May 14 03:57:35 user warn syslog: dns query failed
May 14 03:57:37 user warn syslog: dns query failed
May 14 03:58:11 user warn syslog: dns query failed
May 14 04:08:22 user crit kernel: eth0 Link DOWN.
May 14 04:08:22 user info kernel: br0: port 2(eth0) entering disabled state
May 14 04:12:30 user warn kernel: AdslCoreEcUpdTmr: timeMs=1800230 ecUpdMask=0x40000
May 14 04:42:44 syslog info -- MARK --
May 14 05:42:44 syslog info -- MARK --
May 14 06:04:54 user warn syslog: dns query failed
May 14 06:04:56 user warn syslog: dns query failed
May 14 06:42:44 syslog info -- MARK --
May 14 07:07:31 user warn syslog: dns query failed
May 14 07:07:33 user warn syslog: dns query failed
May 14 07:09:41 user warn syslog: dns query failed
May 14 07:42:44 syslog info -- MARK --
May 14 08:12:19 user warn syslog: dns query failed
May 14 08:12:52 user warn syslog: dns query failed
May 14 08:12:54 user warn syslog: dns query failed
May 14 08:12:56 user warn syslog: dns query failed
May 14 08:42:44 syslog info -- MARK --
May 14 09:15:31 user warn syslog: dns query failed
May 14 09:15:33 user warn syslog: dns query failed
May 14 09:15:35 user warn syslog: dns query failed
May 14 09:16:08 user warn syslog: dns query failed
May 14 09:16:10 user warn syslog: dns query failed
May 14 09:18:17 user warn syslog: dns query failed
May 14 09:18:50 user warn syslog: dns query failed
May 14 09:42:44 syslog info -- MARK --
May 14 09:57:13 user crit kernel: eth0 Link UP.
May 14 09:57:14 user info kernel: br0: port 2(eth0) entering learning state
May 14 09:57:14 user info kernel: br0: topology change detected, propagating
May 14 09:57:14 user info kernel: br0: port 2(eth0) entering forwarding state
May 14 10:19:53 user warn syslog: dns query failed
May 14 10:19:55 user warn syslog: dns query failed
May 14 10:19:57 user warn syslog: dns query failed
May 14 10:20:30 user warn syslog: dns query failed
May 14 10:20:32 user warn syslog: dns query failed
May 14 10:20:34 user warn syslog: dns query failed
May 14 10:22:09 user warn syslog: dns query failed
May 14 10:22:11 user warn syslog: dns query failed
May 14 10:22:13 user warn syslog: dns query failed
May 14 10:22:46 user warn syslog: dns query failed
May 14 10:22:48 user warn syslog: dns query failed
May 14 10:23:21 user warn syslog: dns query failed
May 14 10:23:54 user warn syslog: dns query failed
May 14 10:25:29 user warn syslog: dns query failed
May 14 10:25:31 user warn syslog: dns query failed
May 14 10:25:33 user warn syslog: dns query failed
May 14 10:42:44 syslog info -- MARK --
May 14 10:43:33 user crit kernel: eth0 Link DOWN.
May 14 10:43:33 user info kernel: br0: port 2(eth0) entering disabled state
May 14 10:44:07 user crit kernel: eth0 Link UP.
May 14 10:44:07 user info kernel: br0: port 2(eth0) entering learning state
May 14 10:44:07 user info kernel: br0: topology change detected, propagating
May 14 10:44:07 user info kernel: br0: port 2(eth0) entering forwarding state
May 14 10:44:08 user crit kernel: eth0 Link DOWN.
May 14 10:44:09 user info kernel: br0: port 2(eth0) entering disabled state
May 14 10:44:10 user crit kernel: eth0 Link UP.
May 14 10:44:10 user info kernel: br0: port 2(eth0) entering learning state
May 14 10:44:11 user info kernel: br0: topology change detected, propagating
May 14 10:44:11 user info kernel: br0: port 2(eth0) entering forwarding state
May 14 11:26:04 user warn syslog: dns query failed
May 14 11:26:06 user warn syslog: dns query failed
May 14 11:26:08 user warn syslog: dns query failed
May 14 11:26:41 user warn syslog: dns query failed
May 14 11:26:43 user warn syslog: dns query failed
May 14 11:26:45 user warn syslog: dns query failed
May 14 11:27:18 user warn syslog: dns query failed
May 14 11:27:20 user warn syslog: dns query failed
May 14 11:28:24 user warn syslog: dns query failed
May 14 11:28:57 user warn syslog: dns query failed
May 14 11:28:59 user warn syslog: dns query failed
May 14 11:29:01 user warn syslog: dns query failed
May 14 11:31:07 user warn syslog: dns query failed
May 14 11:31:41 user warn syslog: dns query failed
May 14 11:32:14 user warn syslog: dns query failed
May 14 11:32:16 user warn syslog: dns query failed
May 14 11:32:18 user warn syslog: dns query failed
May 14 11:32:51 user warn syslog: dns query failed
May 14 11:32:53 user warn syslog: dns query failed
May 14 11:32:55 user warn syslog: dns query failed
May 14 11:33:28 user warn syslog: dns query failed
May 14 11:33:30 user warn syslog: dns query failed
May 14 11:33:32 user warn syslog: dns query failed
May 14 11:42:44 syslog info -- MARK --
May 14 12:34:02 user warn syslog: dns query failed
May 14 12:34:36 user warn syslog: dns query failed
May 14 12:34:38 user warn syslog: dns query failed
May 14 12:34:40 user warn syslog: dns query failed
May 14 12:35:13 user warn syslog: dns query failed
May 14 12:36:17 user warn syslog: dns query failed
May 14 12:36:19 user warn syslog: dns query failed
May 14 12:36:21 user warn syslog: dns query failed
May 14 12:37:25 user warn syslog: dns query failed
May 14 12:37:27 user warn syslog: dns query failed
May 14 12:38:01 user warn syslog: dns query failed
May 14 12:38:03 user warn syslog: dns query failed
May 14 12:38:05 user warn syslog: dns query failed
May 14 12:39:40 user warn syslog: dns query failed
May 14 12:40:13 user warn syslog: dns query failed
May 14 12:40:15 user warn syslog: dns query failed
May 14 12:40:17 user warn syslog: dns query failed
May 14 12:40:19 user warn syslog: dns query failed
May 14 12:42:44 syslog info -- MARK --
May 14 12:43:58 user warn syslog: dns query failed
May 14 12:46:04 user warn syslog: dns query failed
May 14 12:48:10 user warn syslog: dns query failed

Будут какие-то соображения?

Проблема где-то на Ethernet-интерфейсе. По логу он периодически отключается и подключается.
Какая сетевая карта на компьютере? Последние ли стоят драйвера?