[Pidgin] #2825: Pidgin cannot reconnect after changing networks

[Pidgin]

#2825: Pidgin cannot reconnect after changing networks
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  Reporter:  novakyu       |       Owner:       
      Type:  defect        |      Status:  new  
  Priority:  minor         |   Milestone:       
 Component:  pidgin (gtk)  |     Version:  2.1.1
Resolution:                |    Keywords:       
   Pending:  0             |  
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Comment (by novakyu):

 I think I finally got it. This is a DNS-related bug. It appears Pidgin (at
 least on GNU/Linux) remembers only the DNS server in use when Pidgin was
 launched and does not re-check /etc/resolv.conf for each new DNS inquiry.
 Here is how I can reproduce the bug every time (no changing of network
 interfaces required):

 1. Set the DNS to a public DNS, like (63.226.12.96), in /etc/resolv.conf.
 Everything works fine, including pinging, web browser, and pidgin
 (launched after setting DNS to the public DNS).

 2. I set an iptables rule blocking outgoing connection to the said DNS
 server (in my particular case, "iptables -A OUTPUT -d 63.226.12.96 -j
 DROP" does the job). Nothing works, such as "nslookup" or web browsing, or
 pidgin (still the same process).

 3. Then, I change my DNS server to my router, (192.168.2.1), in
 /etc/resolv.conf. Everything starts working again, including web browsing.
 But pidgin still does not work.

 4. Then, I delete my iptables rule (with "iptables -D OUTPUT -d
 63.226.12.96 -j DROP"). Pidgin starts working again. I re-instate the rule
 and pidgin can't make new connections.

 5. Finally, I restart Pidgin, and it works fine, even while 63.226.12.96
 is blocked.

 Please let me know if this does not reproduce the same error for anyone
 using GNU/Linux and Pidgin 2.2.2.

-- 
Ticket URL: <http://developer.pidgin.im/ticket/2825#comment:7>
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