Я не обычный сетевой парень ... Я только что призван помочь с этим вопросом, поэтому, пожалуйста, потерпите меня.
У нас довольно большая (~ 4000 устройств?) Сеть, в основном состоящая из оборудования HP Procurve. Время от времени в течение последних нескольких недель мы получали некоторые широковещательные штормы, которые в значительной степени препятствуют отправке всего остального трафика по сети. Я настроил Wireshark для создания дампов по 5 МБ, и кое-что понял сегодня утром.
Вы можете скачать пакет захвата . Веселье началось с пакета № 23968. По-видимому искаженный пакет NBNS повторяется снова и снова. Однако это не просто прямая петля. IP-адреса источника (143.226.8.185) и пункта назначения (143.226.44.79) остаются прежними, но MAC-адрес источника изменяется. Похоже, что первый пакет поступил от какого-то незначительного устройства в сети и отправляется на адрес многоадресной рассылки 01: 00: 5e: 7f: ff: fa. Все пакеты после этого приходят с MAC-адресов наших точек беспроводного доступа HP и отправляются на другой многоадресный адрес, 01: 00: 5e: 62: 2c: 4f.
Вот первый пакет:
No. Time Source Destination Protocol Info
23968 122.229240 143.226.8.185 143.226.44.79 NBNS Unknown operation (10) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding)[Malformed Packet]
Frame 23968 (1038 bytes on wire, 1038 bytes captured)
Arrival Time: Sep 15, 2010 08:32:44.329966000
[Time delta from previous captured frame: 0.004744000 seconds]
[Time delta from previous displayed frame: 0.004744000 seconds]
[Time since reference or first frame: 122.229240000 seconds]
Frame Number: 23968
Frame Length: 1038 bytes
Capture Length: 1038 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:nbns]
[Coloring Rule Name: SMB]
[Coloring Rule String: smb || nbss || nbns || nbipx || ipxsap || netbios]
Ethernet II, Src: IntelCor_d2:5e:6b (00:1f:3b:d2:5e:6b), Dst: IPv4mcast_7f:ff:fa (01:00:5e:7f:ff:fa)
Destination: IPv4mcast_7f:ff:fa (01:00:5e:7f:ff:fa)
Address: IPv4mcast_7f:ff:fa (01:00:5e:7f:ff:fa)
.... ...1 .... .... .... .... = IG bit: Group address (multicast/broadcast)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
Source: IntelCor_d2:5e:6b (00:1f:3b:d2:5e:6b)
Address: IntelCor_d2:5e:6b (00:1f:3b:d2:5e:6b)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
Type: IP (0x0800)
Trailer: 7773643D22687474703A2F2F736368656D61732E786D6C73...
Frame check sequence: 0x6f70653e [incorrect, should be 0x30019938]
Internet Protocol, Src: 143.226.8.185 (143.226.8.185), Dst: 143.226.44.79 (143.226.44.79)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 203
Identification: 0x00d0 (208)
Flags: 0x00
0.. = Reserved bit: Not Set
.0. = Don't fragment: Not Set
..0 = More fragments: Not Set
Fragment offset: 0
Time to live: 128
Protocol: UDP (0x11)
Header checksum: 0xe485 [correct]
[Good: True]
[Bad : False]
Source: 143.226.8.185 (143.226.8.185)
Destination: 143.226.44.79 (143.226.44.79)
User Datagram Protocol, Src Port: netbios-ns (137), Dst Port: netbios-ns (137)
Source port: netbios-ns (137)
Destination port: netbios-ns (137)
Length: 183
Checksum: 0x01db [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
NetBIOS Name Service
Transaction ID: 0x4d2d
Flags: 0x5345 (Unknown operation)
0... .... .... .... = Response: Message is a query
.101 0... .... .... = Opcode: Unknown (10)
.... ..1. .... .... = Truncated: Message is truncated
.... ...1 .... .... = Recursion desired: Do query recursively
.... .... ...0 .... = Broadcast: Not a broadcast packet
Questions: 16722
Answer RRs: 17224
Authority RRs: 8234
Additional RRs: 8264
Queries
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (12081)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (12081)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (11631)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (11631)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25701)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25701)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25914)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25914)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25970)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25970)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (18273)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (18273)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (24953)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (24953)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (26979)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (26979)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (3338)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (3338)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (14882)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (14882)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (28730)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (28730)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25455)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25455)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (8717)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (8717)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (28513)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (28513)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (29287)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (29287)
[Malformed Packet: NBNS]
[Expert Info (Error/Malformed): Malformed Packet (Exception occurred)]
[Message: Malformed Packet (Exception occurred)]
[Severity level: Error]
[Group: Malformed]
Вот следующий пакет:
No. Time Source Destination Protocol Info
23969 122.229836 143.226.8.185 143.226.44.79 NBNS Unknown operation (10) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding) unknown Illegal NetBIOS name (1st character not between A and Z in first-level encoding)[Malformed Packet]
Frame 23969 (217 bytes on wire, 217 bytes captured)
Arrival Time: Sep 15, 2010 08:32:44.330562000
[Time delta from previous captured frame: 0.000596000 seconds]
[Time delta from previous displayed frame: 0.000596000 seconds]
[Time since reference or first frame: 122.229836000 seconds]
Frame Number: 23969
Frame Length: 217 bytes
Capture Length: 217 bytes
[Frame is marked: True]
[Protocols in frame: eth:ip:udp:nbns]
[Coloring Rule Name: SMB]
[Coloring Rule String: smb || nbss || nbns || nbipx || ipxsap || netbios]
Ethernet II, Src: HewlettP_05:de:da (00:17:a4:05:de:da), Dst: IPv4mcast_62:2c:4f (01:00:5e:62:2c:4f)
Destination: IPv4mcast_62:2c:4f (01:00:5e:62:2c:4f)
Address: IPv4mcast_62:2c:4f (01:00:5e:62:2c:4f)
.... ...1 .... .... .... .... = IG bit: Group address (multicast/broadcast)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
Source: HewlettP_05:de:da (00:17:a4:05:de:da)
Address: HewlettP_05:de:da (00:17:a4:05:de:da)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
Type: IP (0x0800)
Internet Protocol, Src: 143.226.8.185 (143.226.8.185), Dst: 143.226.44.79 (143.226.44.79)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 203
Identification: 0x00d0 (208)
Flags: 0x00
0.. = Reserved bit: Not Set
.0. = Don't fragment: Not Set
..0 = More fragments: Not Set
Fragment offset: 0
Time to live: 127
Protocol: UDP (0x11)
Header checksum: 0xe585 [correct]
[Good: True]
[Bad : False]
Source: 143.226.8.185 (143.226.8.185)
Destination: 143.226.44.79 (143.226.44.79)
User Datagram Protocol, Src Port: netbios-ns (137), Dst Port: netbios-ns (137)
Source port: netbios-ns (137)
Destination port: netbios-ns (137)
Length: 183
Checksum: 0x01db [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
NetBIOS Name Service
Transaction ID: 0x4d2d
Flags: 0x5345 (Unknown operation)
0... .... .... .... = Response: Message is a query
.101 0... .... .... = Opcode: Unknown (10)
.... ..1. .... .... = Truncated: Message is truncated
.... ...1 .... .... = Recursion desired: Do query recursively
.... .... ...0 .... = Broadcast: Not a broadcast packet
Questions: 16722
Answer RRs: 17224
Authority RRs: 8234
Additional RRs: 8264
Queries
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (12081)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (12081)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (11631)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (11631)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25701)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25701)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25914)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25914)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25970)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25970)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (18273)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (18273)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (24953)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (24953)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (26979)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (26979)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (3338)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (3338)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (14882)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (14882)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (28730)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (28730)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (25455)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (25455)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (8717)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (8717)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (28513)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (28513)
Illegal NetBIOS name (1st character not between A and Z in first-level encoding): type unknown, class Unknown (29287)
Name: Illegal NetBIOS name (1st character not between A and Z in first-level encoding)
Type: unknown
Class: Unknown (29287)
[Malformed Packet: NBNS]
[Expert Info (Error/Malformed): Malformed Packet (Exception occurred)]
[Message: Malformed Packet (Exception occurred)]
[Severity level: Error]
[Group: Malformed]
Сумасшедший, нет? Если вы посмотрите захват пакета, вы увидите, что большая часть этого пакета повторяется после этой точки. Это продолжается и продолжается, добавляя еще несколько файлов.
Если бы это был цикл, то почему бы только наши точки доступа отправляли этот пакет? Эти точки доступа разбросаны по всему кампусу.
Немного больше информации о нашей сети ... Все плоско. Прямой Ethernet работает на все, и у нас есть блок IP класса B. Нет подсетей. Между нашей сетью и WAN-соединением существует формирователь пакетов, межсетевой экран и маршрутизатор.
Наконец, если вы видите этот пост и он кажется вам знакомым, то это потому, что в прошлом я публиковал аналогичную проблему, которую нам еще предстоит решить, но которую мы еще не видели в последнее время. Это можно найти на коммутаторах HP, отправляющих многоадресные запросы ping .
Большое спасибо за ваше время!
Изменить: Пакет 23968 подтверждается, чтобы быть триггером этого многоадресного шторма. Я воспроизвел этот пакет в нашей сети и снова включил его.
Редактировать / Update:Проведение еще нескольких экспериментов. Я взял одну из наших точек доступа HP и подключил ее непосредственно к своему ПК. Больше ничего не привязано к сегменту. Если я повторю исходный пакет, который вызывал проблемы к AP, AP отвечает один раз. Если я повторю ответ AP обратно к AP, он отвечает снова. Каждый раз, когда это происходит, TTL понижается. Здесь происходит то, что AP в сети первоначально слышат сломанный пакет многоадресной рассылки от хоста и отвечают на него через многоадресную рассылку. Каждый AP слышит эти ответы от всех других AP и отвечает на них. Каждый AP слышит все ответы на ответы и отвечает на них. К счастью, он каждый раз понижает TTL, поэтому шторм уходит, как только TTL достигает 0, и пакет уничтожается. Теперь все, что мне нужно сделать, это выяснить, как остановить это поведение!
Передо мной стоит AP Procruve 420 J8130B.
Изменить (решено!): После попытки, казалось бы, каждого параметра конфигурации на точке доступа, я все еще не мог удержать его от повторной передачи этих многоадресных пакетов. Я обнаружил, что у нас не было последней версии прошивки, поэтому я попытался обновить, но проблема осталась. Затем я попытался перейти на версию 2.1.7 с 29 ноября 2006 года. Никаких проблем с этой прошивкой! AP, работающие 2.1.7, не передают пакет !!! Я все еще жду, чтобы выяснить, как нежелательные данные попали в сеть, но проблема решена на данный момент. Мы делаем сообщение об ошибке с HP.