привет!
Имеется Ubuntu на сервере в качестве роутера. Есть две гигабитные карточки и одна карта Wi-Fi. Одна гигабитная карточка (eth0) & Wi-Fi карточка (wlan0) соединены мостом (br0) и обслуживают внутреннюю сеть. Другая гигабитная карта (eth1) смотрит в интернет через PPPoE (ppp1). По прошествии какого-то времени скорость интернета резко падает с 20Mbps до 4-5Mbps. Помогает "ресет" внешней гигабитной карты eth1:
# poff
# ifconfig eth1 down
# ifconfig eth1 up
# pon provider
После этого скорость снова возвращается на 20Mbps.
Нормальная скорость:

Скорость после некоторого времени:

В ЧЕМ МОЖЕТ БЫТЬ ПРОБЛЕМА?
root@mice:~# lshw -C network
*-network
description: Wireless interface
product: AR93xx Wireless Network Adapter
vendor: Qualcomm Atheros
physical id: 0
bus info: pci@0000:04:00.0
logical name: wlan0
version: 01
serial: cc:b2:55:00:61:e7
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list rom ethernet physical wireless logical
configuration: broadcast=yes driver=ath9k driverversion=3.2.0-54-generic firmware=N/A latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn
resources: irq:19 memory:f7400000-f741ffff memory:f7420000-f742ffff
*-network
description: Ethernet interface
product: DGE-528T Gigabit Ethernet Adapter
vendor: D-Link System Inc
physical id: 0
bus info: pci@0000:06:00.0
logical name: eth1
version: 10
serial: c8:d3:a3:83:d6:20
size: 100Mbit/s
capacity: 1Gbit/s
width: 32 bits
clock: 66MHz
capabilities: pm bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=N/A ip=192.168.0.1 latency=64 link=yes maxlatency=64 mingnt=32 multicast=yes port=MII speed=100Mbit/s
resources: irq:16 ioport:d000(size=256) memory:f7321000-f73210ff memory:f7300000-f731ffff
*-network
description: Ethernet interface
product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:08:00.0
logical name: eth0
version: 06
serial: 54:04:a6:94:fa:3f
size: 1Gbit/s
capacity: 1Gbit/s
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=rtl_nic/rtl8168e-2.fw latency=0 link=yes multicast=yes port=MII speed=1Gbit/s
resources: irq:53 ioport:b000(size=256) memory:f0004000-f0004fff memory:f0000000-f0003fff
root@mice:~# ethtool -i eth1
driver: r8169
version: 2.3LK-NAPI
firmware-version: N/A
bus-info: 0000:06:00.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: yes
root@mice:~# ethtool -i eth0
driver: r8169
version: 2.3LK-NAPI
firmware-version: rtl_nic/rtl8168e-2.fw
bus-info: 0000:08:00.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: yes
root@mice:~# ifconfig
br0 Link encap:Ethernet HWaddr 54:04:a6:94:fa:3f
inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:131967169 errors:0 dropped:211 overruns:0 frame:0
TX packets:63473281 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10000
RX bytes:185459472130 (185.4 GB) TX bytes:34104821610 (34.1 GB)
eth0 Link encap:Ethernet HWaddr 54:04:a6:94:fa:3f
UP BROADCAST RUNNING MULTICAST MTU:9000 Metric:1
RX packets:133960713 errors:0 dropped:0 overruns:0 frame:0
TX packets:56609422 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10000
RX bytes:187446611584 (187.4 GB) TX bytes:23974991524 (23.9 GB)
Interrupt:53 Base address:0x8000
eth1 Link encap:Ethernet HWaddr c8:d3:a3:83:d6:20
inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:25960534 errors:0 dropped:0 overruns:0 frame:0
TX packets:13998750 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10000
RX bytes:32984242119 (32.9 GB) TX bytes:5697859955 (5.6 GB)
Interrupt:16 Base address:0x6000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:604772 errors:0 dropped:0 overruns:0 frame:0
TX packets:604772 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:49406397 (49.4 MB) TX bytes:49406397 (49.4 MB)
mon.wlan0 Link encap:UNSPEC HWaddr CC-B2-55-00-61-E7-00-00-00-00-00-00-00-00-00-00
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2645146 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:441084358 (441.0 MB) TX bytes:0 (0.0 B)
ppp1 Link encap:Point-to-Point Protocol
inet addr:77.51.122.145 P-t-P:77.51.191.254 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:3452429 errors:0 dropped:0 overruns:0 frame:0
TX packets:2626751 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:3668772395 (3.6 GB) TX bytes:1991838011 (1.9 GB)
wlan0 Link encap:Ethernet HWaddr cc:b2:55:00:61:e7
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2252253 errors:0 dropped:0 overruns:0 frame:0
TX packets:6878467 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:10000
RX bytes:130932879 (130.9 MB) TX bytes:10268554923 (10.2 GB)
root@mice:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback
auto domolink
iface domolink inet ppp
pre-up /sbin/ifconfig eth1 up
provider domolink
post-up /etc/cgi-bin/iptables.rules.sh
post-up /sbin/ifconfig ppp1 txqueuelen 10000
auto eth1
iface eth1 inet static
address 192.168.0.1
network 192.168.0.0
netmask 255.255.255.0
broadcast 192.168.0.255
auto br0
iface br0 inet static
address 192.168.1.1
network 192.168.1.0
netmask 255.255.255.0
broadcast 192.168.1.255
bridge-ports eth0 wlan0
dns-nameservers 192.168.1.1 8.8.8.8 8.8.4.4
dns-search intranet
post-up /etc/cgi-bin/post-up.sh
root@mice:~# cat /etc/cgi-bin/post-up.sh
#!/bin/sh
/sbin/ethtool -s eth0 speed 1000 duplex full wol d
/sbin/ethtool -s eth1 speed 100 duplex full wol d
/sbin/ifconfig eth0 mtu 9000
/sbin/ifconfig eth0 txqueuelen 10000
/sbin/ifconfig eth1 txqueuelen 10000
/sbin/ifconfig wlan0 txqueuelen 10000
/sbin/ifconfig br0 txqueuelen 10000
echo 4096 > /proc/sys/net/netfilter/nf_conntrack_expect_max
echo 2 > /proc/sys/net/ipv4/conf/all/arp_ignore
echo 1 > /proc/sys/net/ipv4/conf/all/arp_announce
echo 2048 > /proc/sys/net/ipv4/neigh/default/gc_thresh1
echo 8192 > /proc/sys/net/ipv4/neigh/default/gc_thresh2
echo 16384 > /proc/sys/net/ipv4/neigh/default/gc_thresh3
echo 300 > /proc/sys/net/ipv4/neigh/default/base_reachable_time
service dnsmasq restart
#service smbd restart
service netatalk stop
service netatalk start
ip route add blackhole 192.168.0.0/16
ip route add blackhole 172.16.0.0/12
ip route add blackhole 10.0.0.0/8
route add -net 224.0.0.0/4 dev ppp1
exit 0
root@mice:~# uname -a
Linux mice 3.2.0-54-generic #82-Ubuntu SMP Tue Sep 10 20:08:42 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux