traefik: reverseproxy.go:490: suppressing panic for copyResponse error in test;

Welcome!

Yes, I’ve searched similar issues on GitHub and didn’t find any.
Yes, I’ve searched similar issues on the Traefik community forum and didn’t find any.

What did you do?

After upgrading to latest 2.6.3 (could be unrelated, but it’s the first time I notice this error), I found these errors in the logs:

time="2022-04-06T17:46:34+02:00" level=info msg="Configuration loaded from flags."
2022/04/06 21:08:46 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 296 canceled with error code 268
2022/04/06 21:08:46 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 304 canceled with error code 268

17:46 Apr6 was when I restarted Traefik last time. On that same day at night this happened. It’s a low usage instance, with few users only

Potentially, a movie was being streamed at the time (Jellyfin instance) but that’s only a wild guess at what could have caused this. I don’t even even understand how demanding streaming can be on a reverse proxy.

What did you see instead?

See

What version of Traefik are you using?

2.6.3

What is your environment & configuration?

services:
  traefik:
    image: traefik:v2.6.3
    restart: always
    container_name: "traefik"
    command:
      - --log.filePath=/var/log/traefik.log
      - --log.level=INFO
      - --api.dashboard=true
      - --api.insecure=true
      #      - --api.debug=true
      - --providers.docker=true
      - --providers.docker.endpoint=unix:///var/run/docker.sock
      - --providers.docker.exposedByDefault=false
      - --providers.docker.network=default
      # enable ping healthcheck available at /ping
      - --ping=true
      - --ping.manualrouting=true
      - --providers.file.filename=rules.yml
      - --providers.file.directory=configs
      - --providers.file.watch=true
      # experimental http3
      - --experimental.http3=true
      - --entrypoints.web.address=:80
      - --entrypoints.websecure.address=:443
      - --entrypoints.websecure.http3=true
      - --entrypoints.websecure.http3.advertisedport=443
      - --entryPoints.minecraftudp.address=:25565/udp
      - --entryPoints.minecrafttcp.address=:25565/tcp
      - --entrypoints.web.http.redirections.entryPoint.to=websecure
      - --entrypoints.web.http.redirections.entryPoint.scheme=https
      - --entrypoints.websecure.http.tls.certResolver=le
      - --entrypoints.ssh-alt.address=:2222
      #- --entrypoints.53tcp.address=:53
      #- --entrypoints.53udp.address=:53/udp
      - --entrypoints.vaultwarden-ws.address=:3012
      - --certificatesresolvers.le.acme.dnsChallenge=true
      - --certificatesresolvers.le.acme.dnschallenge.provider=cloudflare
      - --certificatesresolvers.le.acme.storage=/letsencrypt/acme.json
      - --certificatesresolvers.legandi.acme.dnsChallenge=true
      - --certificatesresolvers.legandi.acme.dnschallenge.provider=gandiv5
      - --certificatesresolvers.legandi.acme.storage=/letsencrypt/acme_gandi.json
      # access log section
      - --accesslog=true
      - --accesslog.filepath=/var/log/access.log
      - --accesslog.bufferingsize=10
      - --accesslog.fields.names.StartUTC=drop
    network_mode: host
    #    ports:
    #      - "80:80"
    #      - "443:443"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - $PWD/rules.yml:/configs/rules.yml
      - $PWD/usersfile:/configs/usersfile
      - $PWD/traefik_tls.yml:/configs/traefik_tls.yml
      - /mnt/data/traefik-letsencrypt:/letsencrypt
      - /mnt/data/traefik/log:/var/log
    labels:
      # Dashboard
      traefik.enable: true
      traefik.http.middlewares.secure-headers.headers.sslredirect: "true"
      traefik.http.middlewares.secure-headers.headers.framedeny: "true"
      traefik.http.middlewares.secure-headers.headers.stsincludesubdomains: "true"
      traefik.http.middlewares.secure-headers.headers.stspreload: "true"
      traefik.http.middlewares.secure-headers.headers.stsseconds: "63072000"
      traefik.http.middlewares.secure-headers.headers.contenttypenosniff: "true"
      traefik.http.middlewares.secure-headers.headers.accesscontrolallowmethods: "GET,POST"
      traefik.http.middlewares.secure-headers.headers.accesscontrolalloworiginlist: "*"
      traefik.http.middlewares.secure-headers.headers.accesscontrolmaxage: "100"
      traefik.http.middlewares.secure-headers.headers.addvaryheader: "true"
      traefik.http.middlewares.secure-headers.headers.contentsecuritypolicy: "script-src 'self'"
      traefik.http.middlewares.secure-headers.headers.referrerpolicy: "horigin-when-cross-origin"
      # end

If applicable, please paste the log output in DEBUG level

time="2022-04-06T17:46:34+02:00" level=info msg="Configuration loaded from flags."
2022/04/06 21:08:46 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 296 canceled with error code 268
2022/04/06 21:08:46 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 304 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 308 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 320 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 324 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 328 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 336 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 344 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 356 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 360 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 364 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 368 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 372 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 392 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 396 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 400 canceled with error code 268
2022/04/06 21:08:47 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 404 canceled with error code 268
2022/04/06 21:08:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 416 canceled with error code 268
2022/04/06 21:08:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 420 canceled with error code 268
2022/04/06 21:10:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 440 canceled with error code 268
2022/04/06 21:10:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 504 canceled with error code 268
2022/04/06 21:10:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 508 canceled with error code 268
2022/04/06 21:10:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 516 canceled with error code 268
2022/04/06 21:10:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 520 canceled with error code 268
2022/04/06 21:10:45 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 528 canceled with error code 268
2022/04/06 21:11:41 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 816 canceled with error code 268
2022/04/06 21:11:41 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 820 canceled with error code 268
2022/04/06 21:11:41 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 840 canceled with error code 268
2022/04/06 21:11:41 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 844 canceled with error code 268
2022/04/06 21:11:41 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 848 canceled with error code 268
2022/04/06 21:12:03 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 856 canceled with error code 268
2022/04/06 21:12:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 888 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 892 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 956 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 960 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 964 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 968 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 976 canceled with error code 268
2022/04/06 21:14:58 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 984 canceled with error code 268
2022/04/06 21:15:01 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 992 canceled with error code 268
2022/04/06 21:15:03 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 996 canceled with error code 268
2022/04/06 21:15:03 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1004 canceled with error code 268
2022/04/06 21:15:03 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1008 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1016 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1020 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1028 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1032 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1044 canceled with error code 268
2022/04/06 21:15:04 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1048 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1056 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1064 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1068 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1076 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1084 canceled with error code 268
2022/04/06 21:15:06 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1088 canceled with error code 268
2022/04/06 21:15:07 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1092 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1100 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1104 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1108 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1112 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1124 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1128 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1136 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1140 canceled with error code 268
2022/04/06 21:15:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1148 canceled with error code 268
2022/04/06 21:15:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1156 canceled with error code 268
2022/04/06 21:15:14 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1164 canceled with error code 268
2022/04/06 21:15:19 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1184 canceled with error code 268
2022/04/06 21:15:19 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1188 canceled with error code 268
2022/04/06 21:15:23 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1196 canceled with error code 268
2022/04/06 21:15:23 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1204 canceled with error code 268
2022/04/06 21:15:23 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1208 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1212 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1228 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1236 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1240 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1244 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1248 canceled with error code 268
2022/04/06 21:15:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1252 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1272 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1276 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1280 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1284 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1292 canceled with error code 268
2022/04/06 21:15:48 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1300 canceled with error code 268
2022/04/06 21:16:22 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1312 canceled with error code 268
2022/04/06 21:25:31 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1600 canceled with error code 268
2022/04/06 21:27:00 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1608 canceled with error code 268
2022/04/06 21:27:07 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1776 canceled with error code 268
2022/04/06 21:27:07 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1788 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1792 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1804 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1808 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1812 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1820 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1832 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1836 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1848 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1852 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1856 canceled with error code 268
2022/04/06 21:27:08 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1860 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1868 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1872 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1880 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1884 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1888 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1892 canceled with error code 268
2022/04/06 21:27:09 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1900 canceled with error code 268
2022/04/06 21:27:49 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1908 canceled with error code 268
2022/04/06 21:27:50 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1968 canceled with error code 268
2022/04/06 21:27:50 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1972 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1984 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1988 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 1992 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2000 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2004 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2008 canceled with error code 268
2022/04/06 21:27:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2032 canceled with error code 268
2022/04/06 21:28:26 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2072 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2080 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2084 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2112 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2116 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2120 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2144 canceled with error code 268
2022/04/06 21:28:27 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2164 canceled with error code 268
2022/04/06 21:28:37 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2180 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2184 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2188 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2192 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2208 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2212 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2228 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2232 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2236 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2244 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2248 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2252 canceled with error code 268
2022/04/06 21:28:38 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2256 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2264 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2268 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2272 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2276 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2280 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2284 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2292 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2300 canceled with error code 268
2022/04/06 21:28:39 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2308 canceled with error code 268
2022/04/06 21:29:03 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2316 canceled with error code 268
2022/04/06 21:36:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2532 canceled with error code 268
2022/04/06 21:36:51 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2536 canceled with error code 268
2022/04/06 21:36:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2544 canceled with error code 268
2022/04/06 21:36:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2548 canceled with error code 268
2022/04/06 21:36:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2552 canceled with error code 268
2022/04/06 21:36:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2564 canceled with error code 268
2022/04/06 21:36:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2568 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2572 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2600 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2604 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2620 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2624 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2632 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2636 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2644 canceled with error code 268
2022/04/06 21:36:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2648 canceled with error code 268
2022/04/06 21:37:52 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2656 canceled with error code 268
2022/04/06 21:38:01 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2788 canceled with error code 268
2022/04/06 21:38:01 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2792 canceled with error code 268
2022/04/06 21:38:01 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2796 canceled with error code 268
2022/04/06 21:38:01 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2804 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2820 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2824 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2828 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2832 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2836 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2844 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2848 canceled with error code 268
2022/04/06 21:38:02 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: context canceled
2022/04/06 21:38:24 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2860 canceled with error code 268
2022/04/06 21:38:53 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2900 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2908 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2912 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2916 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2936 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2940 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2964 canceled with error code 268
2022/04/06 21:38:54 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 2984 canceled with error code 268
2022/04/06 21:39:07 reverseproxy.go:490: suppressing panic for copyResponse error in test; copy error: stream 3000 canceled with error code 268

About this issue

Original URL
State: closed
Created 2 years ago
Comments: 15 (5 by maintainers)

Most upvoted comments

This issue is still present in the 2.8 branch of Traefik and appears to be related to the Go standard library implementation of the reverse proxy.

It comes from here: https://cs.opensource.google/go/go/+/master:src/net/http/httputil/reverseproxy.go;l=495 Inside of the httputil.ReverseProxy ServeHTTP method. The log message is printed when there is a response streaming error. The correct behaviour would be for the handler to panic and for the wrapper around it to handle the panic appropriately. It does behave this way when the proxy is used as part of the standard libraries http server, but for other code it defaults to the Go 1.10 behaviour and does not panic, instead logging an error.

This error is spammed to the stdout only because the reverse proxy is invoking Go’s default log package to report the error. There are several ways I can imagine that this issue could be fixed:

Go’s default logger could be configured to discard or write to the standard log.
The logger could be set for the ReverseProxy object so that the message is not sent to the default Go logger.
Traefik could pass a context object to the ReverseProxy handler which has a non-nil object set with the key http.ServerContextKey and handle the panic with error http.ErrAbortHandler gracefully.

Personally I think option 3 is preferable as it mimics the behaviour of the standard library and allows Traefik to react to a request streaming error and output a properly formatted log message. Looking through the code for httputil, setting a context value for http.ServerContextKey should not cause an issue, but that would need to be tested in case there is some upstream issue in a chained handler or something.

niallnsec on Aug 19, 2022

Hey @bt90,

Thank you for the information.

We’ll follow the PR that should fix the issue. We’ll update the dependency to quic-go, and this issue, once a new version with the fix will be released.

Thus you’ll be able to test it.

nmengin on Aug 21, 2023