After upgrade of OCG to version 64050af0456a43344b32e3e93561a79207565eaf, "download as PDF" says there is an error, and the logs in /var/log/ocg/ocg.log say:
```
Jan 26 16:59:23 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5256,"level":50,"err":{"message":"Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED","name":"Error","stack":"Error: Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED\n at RedisClient.on_error (/srv/deployment/ocg/ocg/node_modules/redis/index.js:196:24)\n at Socket.<anonymous> (/srv/deployment/ocg/ocg/node_modules/redis/index.js:106:14)\n at Socket.EventEmitter.emit (events.js:95:17)\n at net.js:441:14\n at process._tickCallback (node.js:415:13)"},"msg":"Redis connection (now disconnected) had error.","time":"2016-01-26T16:59:23.408Z","v":0}
Jan 26 16:59:23 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5251,"level":50,"err":{"message":"Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED","name":"Error","stack":"Error: Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED\n at RedisClient.on_error (/srv/deployment/ocg/ocg/node_modules/redis/index.js:196:24)\n at Socket.<anonymous> (/srv/deployment/ocg/ocg/node_modules/redis/index.js:106:14)\n at Socket.EventEmitter.emit (events.js:95:17)\n at net.js:441:14\n at process._tickCallback (node.js:415:13)"},"msg":"Redis connection (now disconnected) had error.","time":"2016-01-26T16:59:23.529Z","v":0}
Jan 26 16:59:23 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5249,"level":50,"err":{"message":"Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED","name":"Error","stack":"Error: Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED\n at RedisClient.on_error (/srv/deployment/ocg/ocg/node_modules/redis/index.js:196:24)\n at Socket.<anonymous> (/srv/deployment/ocg/ocg/node_modules/redis/index.js:106:14)\n at Socket.EventEmitter.emit (events.js:95:17)\n at net.js:441:14\n at process._tickCallback (node.js:415:13)"},"msg":"Redis connection (now disconnected) had error.","time":"2016-01-26T16:59:23.537Z","v":0}
Jan 26 16:59:23 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5252,"level":50,"err":{"message":"Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED","name":"Error","stack":"Error: Redis connection to deployment-redis01.eqiad.wmflabs:6379 failed - connect ECONNREFUSED\n at RedisClient.on_error (/srv/deployment/ocg/ocg/node_modules/redis/index.js:196:24)\n at Socket.<anonymous> (/srv/deployment/ocg/ocg/node_modules/redis/index.js:106:14)\n at Socket.EventEmitter.emit (events.js:95:17)\n at net.js:441:14\n at process._tickCallback (node.js:415:13)"},"msg":"Redis connection (now disconnected) had error.","time":"2016-01-26T16:59:23.573Z","v":0}
Jan 26 16:59:31 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5251,"level":30,"channel":"frontend.request","request":{"id":"1453827571014-26719","clientip":"127.0.0.1","version":"1.1","method":"GET","url":"/?command=health"},"msg":"Starting request 1453827571014-26719 for 127.0.0.1, HTTP 1.1 GET /?command=health","time":"2016-01-26T16:59:31.015Z","v":0}
Jan 26 16:59:31 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5251,"level":20,"channel":"frontend.request.details","request":{"id":"1453827571014-26719","params":{"command":"health"}},"msg":"Request details for 1453827571014-26719","time":"2016-01-26T16:59:31.016Z","v":0}
Jan 26 16:59:31 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5251,"level":50,"channel":"frontend.error","err":{"message":"send_command: stream not writeable. enable_offline_queue is false","name":"Error","stack":"Error: send_command: stream not writeable. enable_offline_queue is false\n at RedisClient.send_command (/srv/deployment/ocg/ocg/node_modules/redis/index.js:816:39)\n at RedisClient.(anonymous function) (/srv/deployment/ocg/ocg/node_modules/redis/index.js:991:25)\n at /srv/deployment/ocg/ocg/node_modules/prfun/lib/index.js:587:34\n at PrFunPromise.Promise (/srv/deployment/ocg/ocg/node_modules/core-js/modules/es6.promise.js:182:7)\n at new PrFunPromise (/srv/deployment/ocg/ocg/node_modules/prfun/lib/index.js:57:21)\n at /srv/deployment/ocg/ocg/node_modules/prfun/lib/index.js:577:16\n at RedisWrapper.llen (/srv/deployment/ocg/ocg/mw-ocg-service/lib/RedisWrapper.js:132:64)\n at Promise.resolve.then.then.then.responseAry.JobQueue.name (/srv/deployment/ocg/ocg/mw-ocg-service/lib/threads/frontend.js:404:22)\n at run (/srv/deployment/ocg/ocg/node_modules/core-js/modules/es6.promise.js:89:39)\n at /srv/deployment/ocg/ocg/node_modules/core-js/modules/es6.promise.js:100:28"},"request":{"id":"1453827571014-26719"},"msg":"Health failed with error: Error: send_command: stream not writeable. enable_offline_queue is false","time":"2016-01-26T16:59:31.021Z","v":0}
Jan 26 16:59:31 deployment-pdf01 mw-ocg-service: {"name":"mw-ocg-service","hostname":"deployment-pdf01","pid":5251,"level":50,"request":{"id":"1453827571014-26719"},"err":{"message":"Status check failed (redis failure?)","name":"FrontendError","stack":"FrontendError: Status check failed (redis failure?)\n at /srv/deployment/ocg/ocg/mw-ocg-service/lib/threads/frontend.js:438:9\n at run (/srv/deployment/ocg/ocg/node_modules/core-js/modules/es6.promise.js:89:39)\n at /srv/deployment/ocg/ocg/node_modules/core-js/modules/es6.promise.js:100:28\n at process._tickCallback (node.js:415:13)","code":500},"msg":"Status check failed (redis failure?)","time":"2016-01-26T16:59:31.023Z","v":0}
```