Einbahnstraße: kein echo reply nach request


Hallo Zusammen,

habe ein wirklich fieses Problem auf der Arbeit, welches ich euch gerne erläutern würde, da ich hoffe, das jemand von Euch dazu vielleicht etwas einfällt.

Folgendes Problem: Auf ein echo request (gesendet von Server1) an eine IP eines Server2, erfolgt keine echo reply, obwohl der request im System eintrifft.

Dies Verhalten besteht auch bei geleerten ip-table-chains (shorewall clean).

Ping lokal auf den virtuellen Interfaces auf Server2 funktioniert erwartungsgemäß.

Ein cat /proc/sys/net/ipv*/icmp_echo_ignore_all auf Server2 ergibt 0.


Danke im Voraus für eure Mühe und die besten Grüße

Benjamin Casa



Folgend ein paar Auszüge von Konfigurationsdateien und Logs:


// interfaces server2

root@server2:~# cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
address xx.xx.164.82
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95
gateway xx.xx.164.81

dns-search domain.tld

auto eth0:0
iface eth0:0 inet static
address xx.xx.164.83
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

auto eth0:1
iface eth0:1 inet static
address xx.xx.164.84
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:2
iface eth0:2 inet static
address xx.xx.164.85
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:3
iface eth0:3 inet static
address xx.xx.164.86
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:4
iface eth0:4 inet static
address xx.xx.164.87
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:5
iface eth0:5 inet static
address xx.xx.164.88
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:6
iface eth0:6 inet static
address xx.xx.164.89
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

#auto eth0:7
iface eth0:7 inet static
address xx.xx.164.90
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

auto eth0:8
iface eth0:8 inet static
address xx.xx.164.91
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

auto eth0:9
iface eth0:9 inet static
address xx.xx.164.92
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

auto eth0:10
iface eth0:10 inet static
address xx.xx.164.93
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95

auto eth0:11
iface eth0:11 inet static
address xx.xx.164.94
netmask 255.255.255.240
network xx.xx.164.80
broadcast xx.xx.164.95


// ifconfig von server2

root@server2:~# ifconfig
eth0 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.82 Bcast:xx.xx.164.95 Maske:255.255.255.240
inet6 Adresse: fe80::xxxx:xxxx:xxxx:c00/64 Gültigkeitsbereich:Verbindung
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:98353257 errors:0 dropped:0 overruns:0 frame:0
TX packets:6732426 errors:0 dropped:0 overruns:0 carrier:0
Kollisionen:0 Sendewarteschlangenlänge:1000
RX bytes:2816903543 (2.6 GiB) TX bytes:1027636319 (980.0 MiB)
Interrupt:22 Basisadresse:0x4c00

eth0:0 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.83 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

eth0:1 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.84 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

eth0:8 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.91 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

eth0:9 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.92 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

eth0:10 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.93 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

eth0:11 Protokoll:Ethernet Hardware Adresse 00:xx:xx:xx:xx:00
inet Adresse:xx.xx.164.94 Bcast:xx.xx.164.95 Maske:255.255.255.240
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:22 Basisadresse:0x4c00

lo Protokoll:Lokale Schleife
inet Adresse:127.0.0.1 Maske:255.0.0.0
inet6 Adresse: ::1/128 Gültigkeitsbereich:Maschine
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:16415596 errors:0 dropped:0 overruns:0 frame:0
TX packets:16415596 errors:0 dropped:0 overruns:0 carrier:0
Kollisionen:0 Sendewarteschlangenlänge:0
RX bytes:3954625213 (3.6 GiB) TX bytes:3954625213 (3.6 GiB)


// route -n server2

root@server2:/etc/network# route -n
Kernel IP Routentabelle
Ziel Router Genmask Flags Metric Ref Use Iface
xx.xx.164.80 0.0.0.0 255.255.255.240 U 0 0 0 eth0
0.0.0.0 xx.xx.164.81 0.0.0.0 UG 0 0 0 eth0


// ping von Server1

[root@server1:~]$ for i in 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 ; do ping xx.xx.164.$i -w 1 ; done

PING xx.xx.164.81 (xx.xx.164.81) 56(84) bytes of data.
64 bytes from xx.xx.164.81: icmp_seq=1 ttl=252 time=10.0 ms
--- xx.xx.164.81 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 10.038/10.038/10.038/0.000 ms

PING xx.xx.164.82 (xx.xx.164.82) 56(84) bytes of data.
64 bytes from xx.xx.164.82: icmp_seq=1 ttl=60 time=9.77 ms
--- xx.xx.164.82 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 9.773/9.773/9.773/0.000 ms

PING xx.xx.164.83 (xx.xx.164.83) 56(84) bytes of data.
64 bytes from xx.xx.164.83: icmp_seq=1 ttl=60 time=9.72 ms
--- xx.xx.164.83 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 9.729/9.729/9.729/0.000 ms

PING xx.xx.164.84 (xx.xx.164.84) 56(84) bytes of data.
--- xx.xx.164.84 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms

PING xx.xx.164.85 (xx.xx.164.85) 56(84) bytes of data.
--- xx.xx.164.85 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.86 (xx.xx.164.86) 56(84) bytes of data.
--- xx.xx.164.86 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.87 (xx.xx.164.87) 56(84) bytes of data.
--- xx.xx.164.87 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.88 (xx.xx.164.88) 56(84) bytes of data.
--- xx.xx.164.88 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.89 (xx.xx.164.89) 56(84) bytes of data.
--- xx.xx.164.89 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.90 (xx.xx.164.90) 56(84) bytes of data.
--- xx.xx.164.90 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms


PING xx.xx.164.91 (xx.xx.164.91) 56(84) bytes of data.
--- xx.xx.164.91 ping statistics --- [11:54]
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.92 (xx.xx.164.92) 56(84) bytes of data.
--- xx.xx.164.92 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.93 (xx.xx.164.93) 56(84) bytes of data.
--- xx.xx.164.93 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.94 (xx.xx.164.94) 56(84) bytes of data.
--- xx.xx.164.94 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms

PING xx.xx.164.95 (xx.xx.164.95) 56(84) bytes of data.
--- xx.xx.164.95 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1000ms


// tcpdump von Server2

root@server2:~# tcpdump -n -i eth0 | grep xx.xx.52.73
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes

11:53:47.446792 IP xx.xx.52.73 > xx.xx.164.82: icmp 64: echo request seq 1
11:53:47.446826 IP xx.xx.164.82 > xx.xx.52.73: icmp 64: echo reply seq 1
11:53:48.450626 IP xx.xx.52.73 > xx.xx.164.83: icmp 64: echo request seq 1
11:53:48.450657 IP xx.xx.164.83 > xx.xx.52.73: icmp 64: echo reply seq 1
11:53:49.454626 IP xx.xx.52.73 > xx.xx.164.84: icmp 64: echo request seq 1
11:53:56.506412 IP xx.xx.52.73 > xx.xx.164.91: icmp 64: echo request seq 1
11:53:57.507129 IP xx.xx.52.73 > xx.xx.164.91: icmp 64: echo request seq 2
11:53:57.514440 IP xx.xx.52.73 > xx.xx.164.92: icmp 64: echo request seq 1
11:53:58.515070 IP xx.xx.52.73 > xx.xx.164.92: icmp 64: echo request seq 2
11:53:58.522185 IP xx.xx.52.73 > xx.xx.164.93: icmp 64: echo request seq 1
11:53:59.523003 IP xx.xx.52.73 > xx.xx.164.93: icmp 64: echo request seq 2
11:53:59.530211 IP xx.xx.52.73 > xx.xx.164.94: icmp 64: echo request seq 1
11:54:00.530997 IP xx.xx.52.73 > xx.xx.164.94: icmp 64: echo request seq 2
.

Relevant Pages