Reddit's IP unreachable

Question

I'm running Ubuntu.

dig @8.8.8.8 www.reddit.com

; <<>> DiG 9.8.1-P1 <<>> @8.8.8.8 www.reddit.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 46100
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.reddit.com.            IN  A

;; ANSWER SECTION:
www.reddit.com.     3586    IN  CNAME   reddit.com.edgesuite.net.
reddit.com.edgesuite.net. 21587 IN  CNAME   a659.b.akamai.net.
a659.b.akamai.net.  7   IN  A   5.178.40.86
a659.b.akamai.net.  7   IN  A   5.178.40.65

;; Query time: 116 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Thu Mar 21 14:10:19 2013
;; MSG SIZE  rcvd: 130

When I try to connect to Reddit, I get the network unreachable error.

Traceroute is tragically short:

traceroute to 5.178.40.86 (5.178.40.86), 30 hops max, 60 byte packets
 1  Karachi-Desktop.local (5.32.184.193)  2997.308 ms !H  2997.274 ms !H  2997.259 ms !H

How could it happen? What do I do now?

Answer 1

It appears you are using the Hamachi VPN client. Hamachi uses the 5.0.0.0/8 and 25.0.0.0/8 netwoks for its VPN.

However these have not been allocated to Hamachi, and as you have discovered, are in use by real websites. When you attempt to go one of these networks, the packet is intercepted by the Hamachi client and goes nowhere.

Older versions use 5.0.0.0 and newer versions use 25.0.0.0 (or it is possible you can get allocated a 25.0.0.0 network by reconnecting your client to Hamachi). While 25.0.0.0 is still not allocated to Hamachi, it is less likely to collide as that range is owned by a government organisation.

Uninstalling hamachi will solve this problem.