Hi, I think I've solved this issue. No HTTP/502 so far.
First my loadbalancer config was wrong. Check your named port, check your health conditions on both instances groups and loadbalancer (disable them if necesarry to troubleshoot). I also applied the following tuning : - enable gzip (already was) - increase timeout in Nginx - add GCP IP ranges to firewall rules. Take a look to the same blog from Percy.io, thanks to him. https://blog.percy.io/tuning-nginx-behind-google-cloud-platform-http-s-load-balancer-305982ddb340 Cheers Le vendredi 10 mars 2017 08:00:37 UTC-5, Jorge Barrachina a écrit : > > Description of the problem : > > HTTP Cloud load Balancer 502 intermittent responses , doesn’t let request > reach our backend services. It seems that this problem rise up randomly . > Maybe related with > https://groups.google.com/forum/#!topic/google-appengine-downtime-notify/C_fCwHb73wc > > issued on February, 4th? > > Also, we were looking for alternative solutions and we’ve found this post > , that maybe has some correlation with this issue, and bring some light to > find what happened > > > https://blog.percy.io/tuning-nginx-behind-google-cloud-platform-http-s-load-balancer-305982ddb340#.rw4tbv6gl > > > > Issue date periods: > > March 9th, from 14:12:29.697 ( UTC/GMT +1 hour ) till March 10th, > 09:28:36.085 ( UTC/GMT +1 hour ) > > Projects affected : > > oa-staging > > Services affected: > > clientaccount ( versions: release-2017-10-a , release-2017-8-a , > release-2017-07-a) > > > Service url : > > https://clientaccount-dot-oa-staging.appspot-preview.com > > > Deployment Details of our stack : > > > app.yaml > > api_version: 1 > > service: clientaccount > > runtime: python > > env: flex > > entrypoint: gunicorn 'client_account.wsgi:load_app("prod")' > > runtime_config: > > python_version: 3 > > automatic_scaling: > > min_num_instances: 1 > > max_num_instances: 5 > > cool_down_period_sec: 120 # default value > > cpu_utilization: > > target_utilization: 0.8 > > > requirements.txt > > bingads==v10.4.11 > > boto3==1.3.0 > > botocore==1.4.10 > > docutils==0.12 > > Flask==0.10.1 > > Flask-Cors==2.1.2 > > Flask-Security==1.7.5 > > flask-swagger==0.2.12 > > gcloud==0.13.0 > > google-api-python-client==1.5.0 > > googleads==5.0.0 > > gunicorn==19.4.1 > > itsdangerous==0.24 > > Jinja2==2.8 > > jmespath==0.9.0 > > MarkupSafe==0.23 > > mongoengine==0.10.6 > > pymongo==3.2.2 > > python-dateutil==2.5.2 > > PyYAML==3.11 > > recurly==2.4.2 > > requests==2.9.1 > > sendgrid==3.0.1 > > six==1.10.0 > > Werkzeug==0.11.4 > > wheel==0.24.0 > > > Transaction Example Details : > > > If you want to check the transaction on Google Cloud Console , here is the > link to check it out : > > > > https://console.cloud.google.com/logs/viewer?project=oa-staging&hl=es&minLogLevel=0&expandAll=false&resource=http_load_balancer&advancedFilter=resource.type%3D%22http_load_balancer%22%0Aresource.labels.zone%3D%22global%22%0Aresource.labels.project_id%3D%22oa-staging%22%0Atimestamp%3D%222017-03-09T15:35:43.842872262Z%22%0AinsertId%3D%221snolhbg22kclfq%22×tamp=2017-03-09T15:35:43.842872262Z > > GET > https://clientaccount-dot-oa-staging.appspot-preview.com/check_token/**********LONG_TOKEN************* > > > This request arrives to the HTTP Cloud Load Balancer at : 16:35:43.842 > (Madrid Time) > > > Trace Log of the HTTP Cloud Balancer > > { > > insertId: "1snolhbg22kclfq" > > jsonPayload: { > > statusDetails: "failed_to_connect_to_backend" > > @type: " > type.googleapis.com/google.cloud.loadbalancing.type.LoadBalancerLogEntry" > > > } > > httpRequest: { > > requestMethod: "GET" > > requestUrl: " > https://clientaccount-dot-oa-staging.appspot-preview.com/check_token/*********LONG_TOKEN*************"; > > > > requestSize: "1370" > > status: 502 > > responseSize: "421" > > remoteIp: "34.197.229.75" > > } > > resource: { > > type: "http_load_balancer" > > labels: { > > url_map_name: "" > > forwarding_rule_name: "" > > backend_service_name: "" > > target_proxy_name: "" > > zone: "global" > > project_id: "oa-staging" > > } > > } > > timestamp: "2017-03-09T15:35:43.842872262Z" > > severity: "WARNING" > > logName: "projects/oa-staging/logs/requests" > > } > > > The connection with our backend ( > https://clientaccount-dot-oa-staging.appspot-preview.com ) stopped . If > you look into the jsonPayload of the trace provided , it says > “failed_to_connect_to_backend” so it means that our backend seems to be > not processing the request arriving from the http load balancer. > > This is weird , because we didn’t change our stack and it was working days > before of the date reported. > > Could you tell us what happened , our provide some logs to review with our > team. > > Thanks for your support > > -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/a72b75f0-ae81-4edb-8571-0097e1c098f5%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
