monolithic server is sending bad chunks to Steam for games not in cache

Describe the issue you are having

Steam reports that chunks its getting from the monolithic server on my LAN (10.10.10.220) are bad:

[2020-01-23 15:52:10] HTTP (CDN,64) - edge.steam-dns.top.comcast.net (10.10.10.220:80 / 10.10.10.220:80, host: edge.steam-dns.top.comcast.net): Received 0 (Invalid) HTTP response for depot 250821
[2020-01-23 15:52:10] HTTP (CDN,64) - edge.steam-dns.top.comcast.net (10.10.10.220:80 / 10.10.10.220:80, host: edge.steam-dns.top.comcast.net): Disabling dual-stack for this connection
[2020-01-23 15:52:10] Failed unpacking chunk "62c8c8cdff8a5a41b3bd725662458f3fa576a2ee" from "::ffff:a0a:adc/depot/250821/chunk/62c8c8cdff8a5a41b3bd725662458f3fa576a2ee" (Unpack failed (c:1054848,u:0,b:2097152))

How are you running the container(s)?

docker run --name steamcache --restart=unless-stopped -v /home/lancache/cache:/data/cache -v /home/lancache/logs:/data/logs -v /home/lancache/cachedomains:/data/cachedomains -p 80:80 --detach -e CACHE_MAX_AGE=256d -e CACHE_DISK_SIZE=1024g -e CACHE_MEM_SIZE=2048m --init lancachenet/monolithic:latest

DNS Configuration

I'm running CoreDNS on 10.10.10.224, and have it configured to serve as the SOA for lancache.steamcontent.com, responding with A records for lancache.steamcontent.com.

C:\Users\clee> nslookup lancache.steamcontent.com.
Server:  UnKnown
Address:  10.10.10.224

Name:    lancache.steamcontent.com
Addresses: 10.10.10.220

Output of container(s)

Nothing from the container directly, but my error log shows:

2020/01/23 22:52:11 [error] 1340#1340: *49944 unexpected status code 200 in slice response while reading response header from upstream, client: 172.17.0.1, server: , request: "GET /depot/250821/chunk/d88cab2d478fec1464d4027c8396e71a18b38478 HTTP/1.1", subrequest: "/depot/250821/chunk/d88cab2d478fec1464d4027c8396e71a18b38478", upstream: "http://69.241.50.42:80/depot/250821/chunk/d88cab2d478fec1464d4027c8396e71a18b38478", host: "edge.steam-dns.top.comcast.net"

These appear to be the access log entries showing the cache misses:

[steam] 172.17.0.1 / - - - [23/Jan/2020:22:52:11 +0000] "GET /depot/250821/chunk/5b04ac6980efebd9fc845ae0977d5efd23296da5 HTTP/1.1" 200 1049312 "-" "Valve/Steam HTTP Client 1.0" "MISS" "edge.steam-dns.top.comcast.net" "-"

[steam] 172.17.0.1 / - - - [23/Jan/2020:22:52:11 +0000] "GET /depot/250821/chunk/d88cab2d478fec1464d4027c8396e71a18b38478 HTTP/1.1" 200 1047501 "-" "Valve/Steam HTTP Client 1.0" "MISS" "edge.steam-dns.top.comcast.net" "-"
 ^^^^^ --- error log entry related to this chunk

[steam] 172.17.0.1 / - - - [23/Jan/2020:22:52:11 +0000] "GET /depot/250821/chunk/62c8c8cdff8a5a41b3bd725662458f3fa576a2ee HTTP/1.1" 200 1054848 "-" "Valve/Steam HTTP Client 1.0" "MISS" "edge.steam-dns.top.comcast.net" "-"
 ^^^^ --- the chunk that Steam reports is empty/bad

lancachenet / monolithic