我们在 istio 入口网关后面部署了一个应用程序，可通过 test.domain.com/jenkinscore 访问。我们使用了 istio 1.4.5。域名是为 istio 入口网关服务 IP 创建的。根据以下日志，当我们访问此 URL 时，istio-proxy 会抛出 403 错误：upstream connect error or disconnect/reset before headers. reset reason: connection failure。以下是日志。这种情况只会间歇性发生。重新启动入口网关 pod 后，问题得到解决。有人可以告诉我们这个错误的原因是什么吗？
:42:20.798][46][debug][http] [external/envoy/source/common/http/conn_manager_impl.cc:259] [C2469] new stream
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:483] [C2469] recv frame type=1
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][debug][http] [external/envoy/source/common/http/conn_manager_impl.cc:708] [C2469][S10386582713969444678] request headers complete (end_stream=true):
':method', 'GET'
':authority', 'test.domain.com'
':scheme', 'https'
':path', '/jenkinscore'
'cache-control', 'max-age=0'
'upgrade-insecure-requests', '1'
'user-agent', 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36'
'accept', 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9'
'sec-fetch-site', 'cross-site'
'sec-fetch-mode', 'navigate'
'sec-fetch-user', '?1'
'sec-fetch-dest', 'document'
'accept-encoding', 'gzip, deflate, br'
'accept-language', 'en-US,en;q=0.9'
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][debug][http] [external/envoy/source/common/http/conn_manager_impl.cc:1257] [C2469][S10386582713969444678] request end stream
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][debug][jwt] [external/envoy/source/extensions/filters/http/jwt_authn/filter.cc:101] Called Filter : setDecoderFilterCallbacks
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][debug][filter] [src/envoy/http/mixer/filter.cc:47] Called Mixer::Filter : Filter
[Envoy (Epoch 1)] [2020-06-09 11:42:20.798][46][debug][filter] [src/envoy/http/mixer/filter.cc:148] Called Mixer::Filter : setDecoderFilterCallbacks
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][filter] [external/envoy/source/extensions/filters/http/ext_authz/ext_authz.cc:80] [C2469][S10386582713969444678] ext_authz filter calling authorization server
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][router] [external/envoy/source/common/router/router.cc:434] [C0][S9059969016458298666] cluster 'ext_authz' match for URL '/envoy.service.auth.v2.Authorization/Check'
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][router] [external/envoy/source/common/router/router.cc:549] [C0][S9059969016458298666] router decoding headers:
':method', 'POST'
':path', '/envoy.service.auth.v2.Authorization/Check'
':authority', 'ext_authz'
':scheme', 'http'
'te', 'trailers'
'grpc-timeout', '10000m'
'content-type', 'application/grpc'
'x-b3-traceid', 'a4xxxx3471f0f7496063d056b2d9'
'x-b3-spanid', '7a236se1c6c190'
'x-b3-parentspanid', 'f7496063d056b2d9'
'x-b3-sampled', '0'
'x-envoy-internal', 'true'
'x-forwarded-for', '10.48.3.5'
'x-envoy-expected-rq-timeout-ms', '10000'
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][client] [external/envoy/source/common/http/codec_client.cc:31] [C2470] connecting
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][connection] [external/envoy/source/common/network/connection_impl.cc:711] [C2470] connecting to 127.0.0.1:10003
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][connection] [external/envoy/source/common/network/connection_impl.cc:720] [C2470] connection in progress
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][http2] [external/envoy/source/common/http/http2/codec_impl.cc:912] [C2470] setting stream-level initial window size to 268435456
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][http2] [external/envoy/source/common/http/http2/codec_impl.cc:934] [C2470] updating connection-level initial window size to 268435456
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][pool] [external/envoy/source/common/http/conn_pool_base.cc:20] queueing request due to no available connections
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][router] [external/envoy/source/common/router/router.cc:1475] [C0][S9059969016458298666] buffering 1023 bytes
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http] [external/envoy/source/common/http/conn_manager_impl.cc:966] [C2469][S10386582713969444678] decode headers called: filter=0x559dc3768780 status=4
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:424] [C2469] dispatched 441 bytes
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:666] [C2469] about to send frame type=4, flags=0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:720] [C2469] send data: bytes=15
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:398] [C2469] writing 15 bytes, end_stream false
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:608] [C2469] sent frame type=4
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:666] [C2469] about to send frame type=4, flags=1
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:720] [C2469] send data: bytes=9
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:398] [C2469] writing 9 bytes, end_stream false
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:608] [C2469] sent frame type=4
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:666] [C2469] about to send frame type=8, flags=0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:720] [C2469] send data: bytes=13
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:398] [C2469] writing 13 bytes, end_stream false
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http2] [external/envoy/source/common/http/http2/codec_impl.cc:608] [C2469] sent frame type=8
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:462] [C2469] socket event: 2
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:550] [C2469] write ready
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/extensions/transport_sockets/tls/ssl_socket.cc:259] [C2469] ssl write returns: 37
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:462] [C2470] socket event: 3
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][connection] [external/envoy/source/common/network/connection_impl.cc:550] [C2470] write ready
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][connection] [external/envoy/source/common/network/connection_impl.cc:568] [C2470] delayed connection error: 111
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][connection] [external/envoy/source/common/network/connection_impl.cc:193] [C2470] closing socket: 0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][client] [external/envoy/source/common/http/codec_client.cc:88] [C2470] disconnect. resetting 0 pending requests
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][pool] [external/envoy/source/common/http/http2/conn_pool.cc:152] [C2470] client disconnected
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][router] [external/envoy/source/common/router/router.cc:911] [C0][S9059969016458298666] upstream reset: reset reason connection failure
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][http] [external/envoy/source/common/http/async_client_impl.cc:93] async http request response headers (end_stream=true):
':status', '200'
'content-type', 'application/grpc'
'grpc-status', '14'
'grpc-message', 'upstream connect error or disconnect/reset before headers. reset reason: connection failure'
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][filter] [external/envoy/source/extensions/filters/http/ext_authz/ext_authz.cc:244] [C2469][S10386582713969444678] ext_authz filter rejected the request with an error. Response status code: 403
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][http] [external/envoy/source/common/http/conn_manager_impl.cc:1354] [C2469][S10386582713969444678] Sending local reply with details ext_authz_error
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http] [external/envoy/source/common/http/conn_manager_impl.cc:1441] [C2469][S10386582713969444678] encode headers called: filter=0x559dc3646d20 status=0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http] [external/envoy/source/common/http/conn_manager_impl.cc:1441] [C2469][S10386582713969444678] encode headers called: filter=0x559dc3554730 status=0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][filter] [src/envoy/http/mixer/filter.cc:135] Called Mixer::Filter : encodeHeaders 0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][trace][http] [external/envoy/source/common/http/conn_manager_impl.cc:1441] [C2469][S10386582713969444678] encode headers called: filter=0x559dc35ce1e0 status=0
[Envoy (Epoch 1)] [2020-06-09 11:42:20.799][46][debug][http] [external/envoy/source/common/http/conn_manager_impl.cc:1552] [C2469][S10386582713969444678] encoding headers via codec (end_stream=true):
':status', '403'
'date', 'Tue, 09 Jun 2020 11:42:20 GMT'
'server', 'istio-envoy'
答案1
正如我在评论中提到的
Envoy 文档说那
错误状态 设置当过滤器与授权服务器之间发生网络错误时返回给客户端的 HTTP 状态。默认状态为 HTTP 403 Forbidden。
如上所述这里
外部授权过滤器调用授权服务来检查传入请求是否被授权。该过滤器可以配置为网络过滤器或 HTTP 过滤器，或者两者兼而有之。如果网络过滤器认为该请求未经授权，则连接将被关闭。如果 HTTP 过滤器认为该请求未经授权，则请求将被拒绝，并返回 403（禁止）响应。
最近我发现教程这可能会有所帮助，因为他们为 istio 设置了一个外部授权服务器。
在此设置中，ingresss-gateway 将首先将入站请求标头发送到另一个 istio 服务，该服务检查远程用户/客户端提交的标头值。如果标头值通过某些标准，外部授权服务器将指示授权服务器继续向上游发送请求。
我建议看一下这个教程并检查 istio 和外部授权中的所有内容是否配置正确。
提示-> 建议将这些过滤器配置为过滤器链中的第一个过滤器，以便在其余过滤器处理请求之前授权请求。
外部授权服务集群可以静态配置，也可以通过集群发现服务进行配置。如果请求进入时外部服务不可用，则请求是否获得授权由适用网络过滤器或 HTTP 过滤器中的 Failure_mode_allow 配置设置定义。如果设置为 True，则允许请求（失败打开），否则将拒绝请求。默认设置为 false。
我想到的另外一件事可能是故障模式如果 grpc 服务获取upstream connect error or disconnect/reset before headers. reset reason: connection failure，在 istio 中会出现 503 错误。因此，如果您查看下面的第 2 点，ext-authz will reject client requests and return a Forbidden response if the communication the authorization service has returned a HTTP 5xx error那么也许值得尝试将其更改为 true？应该可以使用特使过滤器。
Failure_mode_allow (bool) 改变过滤器在发生错误时的行为：
- 当设置为 true 时，即使与授权服务的通信失败，或者授权服务返回 HTTP 5xx 错误，过滤器也会接受客户端请求。
- 当设置为 false 时，如果与授权服务的通信失败，或者授权服务返回 HTTP 5xx 错误，ext-authz 将拒绝客户端请求并返回 Forbidden 响应。
希望这可以帮助。