Comment 21 for bug 155393

I tried to ping some internet addresses and got some "interesting" results...

~$ping -c 3 www.ubuntu.com
PING www.ubuntu.com (91.189.94.199) 56(84) bytes of data.
64 bytes from www.ubuntu.com (91.189.94.199): icmp_seq=1 ttl=42 time=79.0 ms
64 bytes from www.ubuntu.com (91.189.94.199): icmp_seq=2 ttl=42 time=78.8 ms
64 bytes from www.ubuntu.com (91.189.94.199): icmp_seq=3 ttl=42 time=82.1 ms

--- www.ubuntu.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2001ms
rtt min/avg/max/mdev = 78.875/80.016/82.128/1.495 ms

~$ ping -c 3 archive.canonical.com
PING archive.canonical.com (91.189.90.142) 56(84) bytes of data.
64 bytes from archive.canonical.com (91.189.90.142): icmp_seq=1 ttl=42 time=83.8 ms
64 bytes from archive.canonical.com (91.189.90.142): icmp_seq=2 ttl=42 time=79.7 ms
64 bytes from archive.canonical.com (91.189.90.142): icmp_seq=3 ttl=42 time=83.5 ms

--- archive.canonical.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2003ms
rtt min/avg/max/mdev = 79.768/82.390/83.868/1.873 ms

~$ ping -c 3 archive.ubuntu.com
PING archive.ubuntu.com (1.0.0.0) 56(84) bytes of data.

--- archive.ubuntu.com ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2009ms

1) While I can ping www.ubuntu.com and archive.canonical.com normally, I can't ping archive.ubuntu.com!!!

2) Why Synaptic Package Manager cannot download from the repositories, while I CAN ping archive.ubuntu.com???