Why Puma rails server only accepts localhost:3000 rather than 127.0.0.1:3000

Question

Trying out Puma as my Rails server.

Anybody know why the Puma rails server only accepts localhost:3000 rather than 127.0.0.1:3000?

I'm going to want to test Facebook OAuth, and that will need an IP address.

Same question / duplicate: https://stackoverflow.com/q/27768479 — tanius, Dec 08 '18 at 03:04

score 16 · Answer 1 · answered Feb 17 '15 at 16:42

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Have you tried rails s -b 127.0.0.1 -p 3000? That's always worked for me.

answered Feb 17 '15 at 16:42

Cody Duval

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score 1 · Answer 2 · answered Apr 06 '17 at 06:51

1

Try env PORT=port_number rails s -b your_IP_Address And the server will start on https://your_IP_Address:port_number

answered Apr 06 '17 at 06:51

dArK kNiGhT

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perfect! works on rails 7 too. – spnkr Jan 21 '22 at 02:33

score 0 · Answer 3 · answered Dec 08 '18 at 03:03

This problem was Puma issue #782 and was solved on July 18, 2016 with this patch.

Details: The problem you see is that Puma by default binds to localhost, which was treated as a normal hostname by the underlying Rails TcpServer and there resolved to only one IP address (the IPv6 version in your case) but not to both the IPv4 and IPv6 versions. Due to this, it was not accepting connections on 127.0.0.1:3000 as you saw. In current versions however, an exception is made specifically for localhost, which now binds to both the IPv4 and IPv6 resolutions.

Why Puma rails server only accepts localhost:3000 rather than 127.0.0.1:3000

3 Answers3