Server cannot connect to anything outside of the LAN

Question

I'm trying to set up Ubuntu Server. During the installation, it says "Network autoconfiguration failed" when I try to use DHCP. This is odd because my Ubuntu laptop on the same network can use DHCP with no apparent problems.

If I configure the network settings manually, using the same network settings as my laptop except with a different IP address, I can connect to other machines on the network but not to the Internet.

Here's some diagnostic information, comparing my working laptop with my non-working server:

Laptop

$ ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 88:ae:1d:e6:ec:de  
          inet addr:10.0.53.35  Bcast:10.0.53.255  Mask:255.255.255.0
          inet6 addr: fe80::8aae:1dff:fee6:ecde/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:21888 errors:0 dropped:60 overruns:0 frame:0
          TX packets:14328 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:25901268 (25.9 MB)  TX bytes:1353862 (1.3 MB)

$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.53.254     0.0.0.0         UG    0      0        0 eth0
10.0.53.0       0.0.0.0         255.255.255.0   U     1      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 eth0

$ ping -c 4 10.0.53.254
PING 10.0.53.254 (10.0.53.254) 56(84) bytes of data.
64 bytes from 10.0.53.254: icmp_req=1 ttl=64 time=0.673 ms
64 bytes from 10.0.53.254: icmp_req=2 ttl=64 time=0.493 ms
64 bytes from 10.0.53.254: icmp_req=3 ttl=64 time=0.562 ms
64 bytes from 10.0.53.254: icmp_req=4 ttl=64 time=0.534 ms

--- 10.0.53.254 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2998ms
rtt min/avg/max/mdev = 0.493/0.565/0.673/0.070 ms

Server

$ ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:0d:61:31:d8:38  
          inet addr:10.0.53.153  Bcast:10.0.53.255  Mask:255.255.255.0
          inet6 addr: fe80::20d:61ff:fe31:d838/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:419 errors:0 dropped:65 overruns:0 frame:0
          TX packets:259 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:31975 (31.9 KB)  TX bytes:21581 (21.5 KB)

$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.53.254     0.0.0.0         UG    0      0        0 eth0
10.0.53.0       0.0.0.0         255.255.255.0   U     0      0        0 eth0

$ ping -c 4 10.0.53.254
PING 10.0.53.254 (10.0.53.254) 56(84) bytes of data.

--- 10.0.53.254 ping statistics ---
4 packets transmitted, 0 received, 100% packet loss, time 2999ms