Varnish:使用Nginx + Docker时后端获取失败

Question

我有点迷茫，因为我在docker-compose容器中使用的时候遇到了一个带有Varnish的503-error。

varnishlog返回以下内容：

varnish_1  | *   << BeReq    >> 3
varnish_1  | -   Begin          bereq 2 pass
varnish_1  | -   Timestamp      Start: 1503505759.849314 0.000000 0.000000
varnish_1  | -   BereqMethod    GET
varnish_1  | -   BereqURL       /
varnish_1  | -   BereqProtocol  HTTP/1.1
varnish_1  | -   BereqHeader    Host: localhost
varnish_1  | -   BereqHeader    Pragma: no-cache
varnish_1  | -   BereqHeader    Cache-Control: no-cache
varnish_1  | -   BereqHeader    Upgrade-Insecure-Requests: 1
varnish_1  | -   BereqHeader    User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.101 Safari/537.36
varnish_1  | -   BereqHeader    Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
varnish_1  | -   BereqHeader    Accept-Encoding: gzip, deflate, br
varnish_1  | -   BereqHeader    Accept-Language: de,de-DE;q=0.8,en-US;q=0.6,en;q=0.4
varnish_1  | -   BereqHeader    X-Forwarded-For: 172.18.0.1, 172.18.0.1
varnish_1  | -   BereqHeader    Via: varnish-default
varnish_1  | -   BereqHeader    startedAt: 1503505759.849
varnish_1  | -   BereqHeader    X-Varnish: 3
varnish_1  | -   VCL_call       BACKEND_FETCH
varnish_1  | -   VCL_return     fetch
varnish_1  | -   FetchError     no backend connection
varnish_1  | -   Timestamp      Beresp: 1503505759.849366 0.000052 0.000052
varnish_1  | -   Timestamp      Error: 1503505759.849370 0.000056 0.000004
varnish_1  | -   BerespProtocol HTTP/1.1
varnish_1  | -   BerespStatus   503
varnish_1  | -   BerespReason   Service Unavailable
varnish_1  | -   BerespReason   Backend fetch failed
varnish_1  | -   BerespHeader   Date: Wed, 23 Aug 2017 16:29:19 GMT
varnish_1  | -   BerespHeader   Server: Varnish
varnish_1  | -   VCL_call       BACKEND_ERROR
varnish_1  | -   BerespHeader   Content-Type: text/html; charset=utf-8
varnish_1  | -   BerespHeader   Retry-After: 5
varnish_1  | -   VCL_return     deliver
varnish_1  | -   Storage        malloc Transient
varnish_1  | -   ObjProtocol    HTTP/1.1
varnish_1  | -   ObjStatus      503
varnish_1  | -   ObjReason      Backend fetch failed
varnish_1  | -   ObjHeader      Date: Wed, 23 Aug 2017 16:29:19 GMT
varnish_1  | -   ObjHeader      Server: Varnish
varnish_1  | -   ObjHeader      Content-Type: text/html; charset=utf-8
varnish_1  | -   ObjHeader      Retry-After: 5
varnish_1  | -   Length         278
varnish_1  | -   BereqAcct      0 0 0 0 0 0
varnish_1  | -   End

这是我的default.vcl的内容：

# varnish version 4
vcl 4.0;
import std;
import directors;

# backend start

backend default {
  .host = "web";
  .port = "80";
  .connect_timeout = 30s;
  .first_byte_timeout = 600s;
  .between_bytes_timeout = 1s;
  .probe = {
    .url = "/robots.txt";
    .interval = 10s;
    .timeout = 5s;
    .window = 5;
    .threshold = 3;
  }
}

# backend end


#############
# Housekeeping

# init start
sub vcl_init {
  new magento2 = directors.fallback();
  magento2.add_backend(default);
}
# init end

sub vcl_fini {
  return (ok);
}

#############
# Client side

acl purge {
    "web";
    "php";
    "localhost";
}

sub vcl_recv {
  call custom_ctrl;

  if (req.method == "PURGE") {
      if (client.ip !~ purge) {
          return (synth(405, "Method not allowed"));
      }
      if (!req.http.X-Magento-Tags-Pattern) {
          return (synth(400, "X-Magento-Tags-Pattern header required"));
      }
      ban("obj.http.X-Magento-Tags ~ " + req.http.X-Magento-Tags-Pattern);
      return (synth(200, "Purged"));
  }

  /* We do not support SPDY or HTTP/2.0 */
  if (req.method == "PRI") {
    return (synth(405));
  }

  if (req.restarts == 0) {
    /* set X-Forwarded-For */
    if (req.http.X-Forwarded-For) {
      set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip;
    } else {
      set req.http.X-Forwarded-For = client.ip;
    }
    /* set Via */
    if (req.http.Via) {
      set req.http.Via = req.http.Via + ", varnish-default";
    } else {
      set req.http.Via = "varnish-default";
    }
    set req.http.startedAt = std.time2real(now, 0.0);
  }



  /* backend selector */
  if (req.url ~ "^/max") {
    set req.backend_hint = magento2.backend();
  }

  if (req.method != "GET" &&
    req.method != "HEAD" &&
    req.method != "PUT" &&
    req.method != "POST" &&
    req.method != "TRACE" &&
    req.method != "OPTIONS" &&
    req.method != "DELETE") {
      /* Non-RFC2616 or CONNECT which is weird. */
      return (pipe);
  }

  /* Implementing websocket support (https://www.varnish-cache.org/docs/4.0/users-guide/vcl-example-websockets.html) */
  if (req.http.Upgrade ~ "(?i)websocket") {
    return (pipe);
  }


  if (req.method != "GET" && req.method != "HEAD") {
    /* We only deal with GET and HEAD by default */
    return (pass);
  }

  /* Not cacheable */
  if (req.http.Authorization) {
    return (pass);
  }

  # no cache request
  if (req.http.Cache-Control == "no-cache" || req.url ~ "cache-control=no-cache") {
    return (pass);
  }

  # Send Surrogate-Capability headers to announce ESI support to backend
  # set req.http.Surrogate-Capability = "key=ESI/1.0";

  # sort the query string
  set req.url = std.querysort(req.url);

  # Bypass shopping cart, checkout and search requests
  if (req.url ~ "/checkout" || req.url ~ "/catalogsearch") {
      return (pass);
  }

  # normalize url in case of leading HTTP scheme and domain
  set req.url = regsub(req.url, "^http[s]?://", "");

  # Cookies
  std.collect(req.http.Cookie);

  # Compression filter. See https://www.varnish-cache.org/trac/wiki/FAQ/Compression
  if (req.http.Accept-Encoding) {
      if (req.url ~ "\.(jpg|jpeg|png|gif|gz|tgz|bz2|tbz|mp3|ogg|swf|flv)$") {
          # No point in compressing these
          unset req.http.Accept-Encoding;
      } elsif (req.http.Accept-Encoding ~ "gzip") {
          set req.http.Accept-Encoding = "gzip";
      } elsif (req.http.Accept-Encoding ~ "deflate" && req.http.user-agent !~ "MSIE") {
          set req.http.Accept-Encoding = "deflate";
      } else {
          # unkown algorithm
          unset req.http.Accept-Encoding;
      }
  }
  # Remove Google gclid parameters to minimize the cache objects
  set req.url = regsuball(req.url,"\?gclid=[^&]+$",""); # strips when QS = "?gclid=AAA"
  set req.url = regsuball(req.url,"\?gclid=[^&]+&","?"); # strips when QS = "?gclid=AAA&foo=bar"
  set req.url = regsuball(req.url,"&gclid=[^&]+",""); # strips when QS = "?foo=bar&gclid=AAA" or QS = "?foo=bar&gclid=AAA&bar=baz"

  # static files are always cacheable. remove SSL flag and cookie
  if (req.url ~ "^/(pub/)?(media|static)/.*\.(ico|css|js|jpg|jpeg|png|gif|tiff|bmp|mp3|ogg|svg|swf|woff|woff2|eot|ttf|otf)$") {
    unset req.http.Https;
    unset req.http.X-Forwarded-Proto;
    unset req.http.Cookie;
  }

  return (hash);
}


sub vcl_pipe {
  # By default Connection: close is set on all piped requests, to stop
  # connection reuse from sending future requests directly to the
  # (potentially) wrong backend. If you do want this to happen, you can undo
  # it here.
  # unset bereq.http.connection;
  if (req.http.upgrade) {
    set bereq.http.upgrade = req.http.upgrade;
  }
  return (pipe);
}


sub vcl_pass {
  return (fetch);
}


sub vcl_hash {

  if (req.http.host) {
    hash_data(req.http.host);
  } else {
    hash_data(server.ip);
  }

  if (req.http.cookie ~ "X-Magento-Vary=") {
    hash_data(regsub(req.http.cookie, "^.*?X-Magento-Vary=([^;]+);*.*$", "\1"));
  }

  # For multi site configurations to not cache each other's content
  if (req.http.host) {
    hash_data(req.http.host);
  } else {
    hash_data(server.ip);
  }

  # To make sure http users don't see ssl warning
  if (req.http.X-Forwarded-Proto) {
    hash_data(req.http.X-Forwarded-Proto);
  }

  return (lookup);
}


sub vcl_purge {
  return (synth(200, "Purged"));
}


sub vcl_hit {
  if (obj.ttl > 0s) {
    # A pure unadultered hit, deliver it
    return (deliver);
  }
  # backend is healthy
  if (std.healthy(req.backend_hint)) {
    # set the stale
    if(obj.ttl + std.duration(std.integer(regsub(obj.http.Cache-Control, "[\s\S]*m-stale=(\d)+[\s\S]*", "\1"), 2) + "s", 2s) > 0s){
      return (deliver);
    }
  } else if (obj.ttl + obj.grace > 0s) {
    # Object is in grace, deliver it
    # Automatically triggers a background fetch
    return (deliver);
  }

  # fetch & deliver once we get the result
  return (miss);
}


sub vcl_miss {
  return (fetch);
}


sub vcl_deliver {
  # Happens when we have all the pieces we need, and are about to send the
  # response to the client.
  #
  # You can do accounting or modifying the final object here.
  set resp.http.X-Hits = obj.hits;
  set req.http.varnishUse = now - std.real2time(std.real(req.http.startedAt, 0.0), now);
  if (resp.http.Server-Timing) {
    if (std.real(req.http.varnishUse, 0) > 0) {
      set resp.http.Server-Timing = "9=" + req.http.varnishUse + ";Varnish," + resp.http.Server-Timing;
    } else {
      set resp.http.Server-Timing = "9=0.000;Varnish," + resp.http.Server-Timing;
    }
  } else {
    if (std.real(req.http.varnishUse, 0) > 0) {
      set resp.http.Server-Timing = "9=" + req.http.varnishUse + ";Varnish";
    } else {
      set resp.http.Server-Timing = "9=0.000;Varnish";
    }
  }
  return (deliver);
}



# custom control
sub custom_ctrl{
  #响应healthy检测
  if(req.url == "/ping"){
    return(synth(701));
  }
  if(req.url == "/varnish/version") {
    return(synth(702));
  }
}


sub vcl_synth {
  if (resp.status == 701) {
    synthetic("pong");
  } elsif (resp.status == 702) {
    synthetic("2017-08-20T16:27:55.780Z");
  }
  set resp.http.Cache-Control = "no-store, no-cache, must-revalidate, max-age=0";
  set resp.status = 200;
  set resp.http.Content-Type = "text/plain; charset=utf-8";
  return (deliver);
}


###############
# Backend Fetch

sub vcl_backend_fetch {
  return (fetch);
}



sub vcl_backend_response {
  if (bereq.uncacheable) {
    return (deliver);
  }

  if (beresp.http.content-type ~ "text") {
      set beresp.do_esi = true;
  }

  # cache only successfully responses and 404s
  if (beresp.status != 200 && beresp.status != 404) {
      set beresp.ttl = 0s;
      set beresp.uncacheable = true;
      return (deliver);
  } elsif (beresp.http.Cache-Control ~ "private") {
      set beresp.uncacheable = true;
      set beresp.ttl = 86400s;
      return (deliver);
  }

  if (beresp.http.X-Magento-Debug) {
      set beresp.http.X-Magento-Cache-Control = beresp.http.Cache-Control;
  }

  # validate if we need to cache it and prevent from setting cookie
  # images, css and js are cacheable by default so we have to remove cookie also
  if (beresp.ttl > 0s && (bereq.method == "GET" || bereq.method == "HEAD")) {
      unset beresp.http.set-cookie;
      if (bereq.url !~ "\.(ico|css|js|jpg|jpeg|png|gif|tiff|bmp|gz|tgz|bz2|tbz|mp3|ogg|svg|swf|woff|woff2|eot|ttf|otf)(\?|$)") {
          set beresp.http.Pragma = "no-cache";
          set beresp.http.Expires = "-1";
          set beresp.http.Cache-Control = "no-store, no-cache, must-revalidate, max-age=0";
          set beresp.grace = 1m;
      }
  }

  # the response body is text, do gzip (judge by response header Content-Type)
  if (beresp.http.Content-Type ~ "text" || beresp.http.Content-Type ~ "application/javascript" || beresp.http.Content-Type ~ "application/json") {
    set beresp.do_gzip = true;
  }

  # The following scenarios set uncacheable
  if (beresp.ttl <= 0s ||
    beresp.http.Set-Cookie ||
    beresp.http.Surrogate-Control ~ "no-store" ||
    (!beresp.http.Surrogate-Control &&
      beresp.http.Cache-Control ~ "no-cache|no-store|private") ||
    beresp.http.Vary == "*"){
    # Hit-For-Pass
    set beresp.uncacheable = true;
    set beresp.ttl = 300s;
    set beresp.grace = 0s;
    return (deliver);
  }

  # Pause ESI request and remove Surrogate-Control header
  if (beresp.http.Surrogate-Control ~ "ESI/1.0") {
    unset beresp.http.Surrogate-Control;
    set beresp.do_esi = true;
  }

  return (deliver);
}

您可能想知道为什么在配置中会有.host = "web" -这是因为docker-compose神奇地为链接服务的docker-compose.yml文件中的每个节点创建了配置，在我的例子中是web作为nginx实例的服务名。

我能够从varnish容器ping web，所以链接是正常的。此外，这也是码头容器的首选用途。

nginx正在监听端口80 (就像内部的清漆)。我之前在8080上试过nginx，但它一直在侦听tcp:80，没有错误输出，所以我试着把两个服务都映射到80端口，它似乎工作得很好；但是，如果我把nginx切换到8080端口，问题就存在了。请记住，如果您在Dockerfile文件中为web-container使用FROM nginx，nginx将始终侦听端口80，因此这也可能不是问题。

很乐意提供更多信息。

Answer 1

这个Github问题的答案为我解决了这个问题。看起来，这个调查产生了一些问题。我不知道为什么，但是使用问题本身中标记的较小的配置文件是有效的。

https://github.com/magento/magento2/issues/10165