stop apt looking for srv records
I am trying to use apt on a network that is only intermittently connected to the Internet. The network has a local apt mirror and I have put the ip address of that mirror in all the entries in sources.list.
Unfortunately when disconnected from the Internet there is an annoying delay in running apt commands. Investigating with tcpdump shows.
14:44:52.271437 IP 172.19.0.2.42208 > 8.8.8.8.domain: 180+ SRV? _http._tcp.172.19.0.1. (39)
14:44:57.277063 IP 172.19.0.2.42208 > 8.8.8.8.domain: 180+ SRV? _http._tcp.172.19.0.1. (39)
14:44:57.277160 IP 172.19.0.1 > 172.19.0.2: ICMP net 8.8.8.8 unreachable, length 75
14:45:02.286414 IP 172.19.0.2.42208 > 8.8.8.8.domain: 180+ SRV? _http._tcp.172.19.0.1. (39)
14:45:02.286504 IP 172.19.0.1 > 172.19.0.2: ICMP net 8.8.8.8 unreachable, length 75
Is there any way to stop apt doing this and just make it connect immediately to the local mirror?
Try putting the apt mirror in as the apt proxy.
Create the file if it does not exist:
/etc/apt/apt.conf
Add the apt proxy info:
Acquire::http::Proxy "http://address:port";
or in your case:
Acquire::http::Proxy "http://172.19.0.2.42208";
Don’t forget the ; at the end.
Test by updating:
sudo apt-get update
I am not sure if your mirror will work this way. Perhaps an apt cacher like apt-cacher-ng will help.
If you have a full mirror couldn’t you change the domain name part of the source to your mirror ip address?
Example if the source was:
deb http://ftp.ussg.iu.edu/linux/ubuntu xenial main restricted universe multiverse
Change to:
deb http://172.19.0.2.42208/linux/ubuntu xenial main restricted universe multiverse
Ok I found the answer by reading the sourcecode
Add the following to /etc/apt/apt.conf (create it if it doesn’t exist)
Acquire::EnableSrvRecords "false";