Login Error on Kibana\ElasticSearch console

Question

this morning i can't access to my kibana console, that return me a "Oops! Error. Try again." error from the login page.

Yesterday, the only thing i did

was set number_of_replicas setting of the .apm-agent-configuration index to 0 because i had a lot of replicas not assigned.

This is the log i can read from /var/log/kibana/kibana.log on my kibana server:

{"type":"log","@timestamp":"2022-04-21T12:02:59+02:00","tags":["info","plugins","security","routes"],"pid":1136,"message":"Logging in with provider "basic" (basic)"} {"type":"log","@timestamp":"2022-04-21T12:02:59+02:00","tags":["error","plugins","security","session","index"],"pid":1136,"message":"Failed to create session value: cluster_block_exception"} {"type":"log","@timestamp":"2022-04-21T12:02:59+02:00","tags":["error","http"],"pid":1136,"message":"ResponseError: cluster_block_exception\n at onBody (/usr/share/kibana/node_modules/@elastic/elasticsearch/lib/Transport.js:337:23)\n at IncomingMessage.onEnd (/usr/share/kibana/node_modules/@elastic/elasticsearch/lib/Transport.js:264:11)\n at IncomingMessage.emit (events.js:387:35)\n at endReadableNT (internal/streams/readable.js:1317:12)\n at processTicksAndRejections (internal/process/task_queues.js:82:21) {\n meta: {\n body: { error: [Object], status: 429 },\n statusCode: 429,\n headers: {\n 'content-type': 'application/json; charset=UTF-8',\n 'content-length': '435'\n },\n meta: {\n context: null,\n request: [Object],\n name: 'elasticsearch-js',\n connection: [Object],\n attempts: 0,\n aborted: false\n }\n }\n}"} {"type":"error","@timestamp":"2022-04-21T12:02:59+02:00","tags":[],"pid":1136,"level":"error","error":{"message":"Internal Server Error","name":"Error","stack":"Error: Internal Server Error\n at HapiResponseAdapter.toInternalError (/usr/share/kibana/src/core/server/http/router/response_adapter.js:61:19)\n at Router.handle (/usr/share/kibana/src/core/server/http/router/router.js:177:34)\n at runMicrotasks ()\n at processTicksAndRejections (internal/process/task_queues.js:95:5)\n at handler (/usr/share/kibana/src/core/server/http/router/router.js:124:50)\n at exports.Manager.execute (/usr/share/kibana/node_modules/@hapi/hapi/lib/toolkit.js:60:28)\n at Object.internals.handler (/usr/share/kibana/node_modules/@hapi/hapi/lib/handler.js:46:20)\n at exports.execute (/usr/share/kibana/node_modules/@hapi/hapi/lib/handler.js:31:20)\n at Request._lifecycle (/usr/share/kibana/node_modules/@hapi/hapi/lib/request.js:370:32)\n at Request._execute (/usr/share/kibana/node_modules/@hapi/hapi/lib/request.js:279:9)"},"url":"https://consoleids.enac.gov.it/internal/security/login","message":"Internal Server Error"} {"type":"response","@timestamp":"2022-04-21T12:02:59+02:00","tags":[],"pid":1136,"method":"post","statusCode":500,"req":{"url":"/internal/security/login","method":"post","headers":{"host":"consoleids.enac.gov.it","connection":"keep-alive","content-length":"171","sec-ch-ua":"" Not A;Brand";v="99", "Chromium";v="100", "Google Chrome";v="100"","content-type":"application/json","sec-ch-ua-mobile":"?0","user-agent":"Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.127 Safari/537.36","kbn-version":"7.13.3","sec-ch-ua-platform":""Windows"","accept":"/","origin":"https://consoleids.enac.gov.it","sec-fetch-site":"same-origin","sec-fetch-mode":"cors","sec-fetch-dest":"empty","referer":"https://consoleids.enac.gov.it/login?next=%2F","accept-encoding":"gzip, deflate, br","accept-language":"it-IT,it;q=0.9,en-US;q=0.8,en;q=0.7"},"remoteAddress":"10.144.9.168","userAgent":"Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.127 Safari/537.36","referer":"https://consoleids.enac.gov.it/login?next=%2F"},"res":{"statusCode":500,"responseTime":65,"contentLength":97},"message":"POST /internal/security/login 500 65ms - 97.0B"}

Could u help understand the problem?

Thanks,