We have a React/Django app with docker-compose at work. Any request to localhost takes 8 seconds: ab -n1 http://localhost:8080/

This is ApacheBench, Version 2.3 <$Revision: 1879490 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/

Benchmarking localhost (be patient).....done


Server Software:        WSGIServer/0.2
Server Hostname:        localhost
Server Port:            8080

Document Path:          /
Document Length:        0 bytes

Concurrency Level:      1
Time taken for tests:   8.079 seconds
Complete requests:      1
Failed requests:        0
Non-2xx responses:      1
Total transferred:      768 bytes
HTML transferred:       0 bytes
Requests per second:    0.12 [#/sec] (mean)
Time per request:       8079.369 [ms] (mean)
Time per request:       8079.369 [ms] (mean, across all concurrent requests)
Transfer rate:          0.09 [Kbytes/sec] received

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    0   0.0      0       0
Processing:  8079 8079   0.0   8079    8079
Waiting:     8079 8079   0.0   8079    8079
Total:       8079 8079   0.0   8079    8079

When I check tcpdump output by looking the docker bridge traffic I get:

10:00:29.594195 IP mylaptop.57775 > home.domain: 8575+ [1au] A? host.docker.internal. (49)
10:00:34.679533 IP mylaptop.57775 > home.domain: 8575+ [1au] A? host.docker.internal. (49)
10:00:37.598461 IP mylaptop.41076 > home.domain: 5915+ [1au] A? host.docker.internal.home. (54)
10:00:37.601026 IP home.domain > mylaptop.41076: 5915 NXDomain 0/0/1 (54)
10:00:37.601256 IP mylaptop.41076 > home.domain: 5915+ A? host.docker.internal.home. (43)
10:00:37.602351 IP home.domain > mylaptop.41076: 5915 NXDomain 0/0/0 (43)

This does not happen when I turn-off the wifi, requests are a few ms then. Same as in production.

This problem happened after updating our software stack (Django v3.2 → v4.2, React v16 → v18) but it didn’t affect other coworkers (now they are on vacation).

I have zero networking training so I’m at a loss for what to check next.