All my elastic index are red version 5.5.2

Elastic Stack Elasticsearch
1

hi
I have 3 ELK nodes
i have all my index are red

red   open bgc-2018.12          fHv8O7JmQZa0rnjpB7pFjQ 5 1  76132 0 195.6mb  97.8mb
red   open bgc-2017             dHzBmmj0RZyonRB3r0DvVA 5 1      0 0   1.1kb    573b
red   open bgc-2018.11          DfN2_hIPQ0SfPd5sNCCWfQ 5 1 183082 0 232.5mb 116.2mb
red   open bgc-2017.03          jSO8L_-ZTui40BXgE9uLqg 5 1      0 0   1.2kb    627b
red   open bgc-2018.07          s_q4Ao_pRV6uj8-GwqMR2Q 5 1   3799 0   5.5mb   2.7mb
red   open bgc-2018.02          gDwVM91ARuyyxYGX2P5GjQ 5 1   1983 0   3.3mb   1.6mb
red   open bgc-2017.11          b6xaQj6ISfyY0-46QoMtEA 5 1   7912 0   8.4mb   4.2mb
red   open bgc-2018.01          G-VUqoMpQPGpVhOrCFyxvg 5 1    745 0   1.9mb 997.8kb
red   open bgc-2018.09          TlfrM_cgReeJFO95MdOfSw 5 1  81218 0 160.2mb  80.1mb
red   open bgc-2018.12_mycloud  4lQS7m90TM-uVThEGBijJQ 5 1  38324 0  53.2mb  26.6mb
red   open bgc-2018.10          VZgQSAUBSQmhyJQdp5HMXw 5 1  97583 0  98.1mb    49mb
red   open bgc-2018.04          BBPGL6W5QkeGU7QKPQbsGw 5 1   2841 0   4.7mb   2.3mb
green open .kibana_bgc          6MckZW4KTlu24tt7n6_q-g 1 1    178 2 377.9kb 188.9kb
red   open bgc                  ljfD5QATQoyeIB7VzxSZdA 5 1      1 0     8kb     4kb
red   open bgc-2017.10          5NdSJuEnQMuPTlrpvxryPQ 5 1   5653 0   7.4mb   3.7mb
red   open bgc-2018.08          tANrAIfpT_y-Mpw-XY3pIg 5 1  20134 0  24.4mb  12.2mb
red   open bgc-2017.08          GfLRBK_KSju1gBxdKnh57w 5 1    278 0 684.3kb 342.1kb
red   open bgc-2018.11_version2 uKcmFbIyRY-j4f9-qKTHKw 5 1 105698 0 122.8mb  61.4mb
green open kibana_bgc           WstuPBrPQm-735ZQCQmj3w 1 1      6 1 110.4kb  55.2kb
red   open bgc-2017.07          yNdMNxs9TbCsV5FrHxd60Q 5 1   7302 0   7.7mb   3.8mb
red   open bgc-2017.05          XuJmreaMQxWJAxs_MXs7gg 5 1   8572 0  10.6mb   5.3mb
red   open bgc-2018.03          gMXcVwZoRByf-_bMnv4iRw 5 1   2429 0   3.7mb   1.8mb
red   open bgc-2017.06          jUSC657lR9m0tnQMDIMXFA 5 1  43948 0  39.9mb  19.9mb
red   open bgc-2018.06          YBYwFbi6R6OINLkst2g_sA 5 1   2817 0   4.4mb   2.2mb
red   open bgc-2018.11_vesrion1 6tBBZCt1QRKbxUJnAJqMcA 5 1 293197 0 323.9mb 161.9mb
red   open bgc-2018.05          _2pfuJgiRFGw913XuK7k8w 5 1   3378 0   5.2mb   2.6mb
red   open bgc-2017.12          PKCDMjJLRYiKPmksWCZ_qA 5 1   8485 0  10.2mb   5.1mb
red   open bgc-2017.04          4D6P0imXRZy6hQEwRG-3iA 5 1      4 0  57.2kb  28.6kb

when i try with _cluster/allocation/explain?pretty
allocate_explanation "cannot allocate because a previous copy of the primary shard existed but can no longer be found on the nodes in the cluster"

and when i try with curl -XPOST 'http://bgc-elastic.bench.mycloud.intranatixis.com/_cluster/reroute?pretty' -d '{"commands" : [

{"allocate_stale_primary" :{"index" : "bgc-2017.03", "shard" : 3,"node" : "swbcfregb256","accept_data_loss" : true}}]}'
{
  "error" : {
    "root_cause" : [
      {
        "type" : "remote_transport_exception",
        "reason" : "[swbcfregb847][100.83.122.169:9300][cluster:admin/reroute]"
      }
    ],
    "type" : "illegal_argument_exception",
    "reason" : "[allocate_stale_primary] primary [bgc-2017.03][3] is already assigned"
  },
  "status" : 400
}

can you help me please to have green status

2

You probably lost 2 nodes and some primaries are now missing.

You need to recover the 2 nodes otherwise you won't be able to get back your indices.

By the way, you are using too many shards for a very small amount of data IMO.
1 primary shard per index should be enough. Even more, one single index per year is also probably enough, but it's up to you...