Debian/Ubuntu - No network connection
- by leviathanus
I have a very weird situation on my Ubuntu 12.04 LTS Server. I can not access (ping) my gateway, although I believe my config is ok - I attach the outputs. Any hints where to look?
(I changed the beginning of the IP to something different, just obfuscation)
ping 5.9.10.129
PING 5.9.10.129 (5.9.10.129) 56(84) bytes of data.
From 5.9.10.129 (5.9.10.129) icmp_seq=2 Destination Host Unreachable
From 5.9.10.129 (5.9.10.129) icmp_seq=3 Destination Host Unreachable
From 5.9.10.129 (5.9.10.129) icmp_seq=4 Destination Host Unreachable
uname -r
3.2.0-29-generic
ifconfig eth0
eth0 Link encap:Ethernet HWaddr 3c:97:0e:0e:54:d7
inet addr:5.9.10.142 Bcast:5.9.10.159 Mask:255.255.255.224
inet6 addr: fe80::8e70:5aff:feda:c4ac/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1216 errors:0 dropped:0 overruns:0 frame:0
TX packets:490 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:107470 (107.4 KB) TX bytes:34344 (34.3 KB)
Interrupt:17 Memory:d2500000-d2520000
ip route
default via 5.9.10.129 dev eth0 metric 100
5.9.10.128/27 via 5.9.10.129 dev eth0
5.9.10.128/27 dev eth0 proto kernel scope link src 5.9.10.142
route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 5.9.10.129 0.0.0.0 UG 1000 0 0 eth0
5.9.10.128 5.9.10.129 255.255.255.224 UG 0 0 0 eth0
5.9.10.128 0.0.0.0 255.255.255.224 U 0 0 0 eth0
iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT) target prot opt source destination
UPD: Eric, this is how routing information looks on a working server:
0.0.0.0 78.47.198.49 0.0.0.0 UG 100 0 0 eth0
78.47.198.48 78.47.198.49 255.255.255.240 UG 0 0 0 eth0
78.47.198.48 0.0.0.0 255.255.255.240 U 0 0 0 eth0
As I understand it, Hetzner tries to ensure security by this, so I can not take over an IP by changing my MAC. But this is another server, which has another netmask (255.255.255.240)
UPD2: BatchyX,
on the working server:
78.47.198.49 dev eth0 src 78.47.198.60
cache
on the broken:
5.9.10.129 dev eth0 src 5.9.10.142
cache
