.ml-anomalies-* indices not listed in _cat/indices/_all but it is listed in _cat/indices/.ml-anomalies-*?

[bertr (Bert Rietveld)]

Version 7.8.1
ML is working properly, but I don't see the .ml-anomalies-* indices listed when running _cat/indices/_all? The indices also dont show in Index Management screen, but I can/could create an index pattern .ml-anomalies-*. Then _cat/indices/.ml-anomalies-* does show the index:

_cat/indices/_all?v&s=index:

health status index                               uuid                   pri rep docs.count docs.deleted store.size pri.store.size
green  open   .apm-agent-configuration            nK-OR2X6Qcq8wC49xlVR4g   1   0          0            0       208b           208b
green  open   .apm-custom-link                    ozlFeg9JQn6_CYvX8a03vQ   1   0          0            0       208b           208b
green  open   .async-search                       uvGDZhmARWqUltiabfyJTg   1   0         35           17     45.6mb         45.6mb
green  open   .kibana-event-log-7.8.1-000001      Ypo-coN6QGCKYxsuvHa8qg   1   0       2108            0    286.7kb        286.7kb
green  open   .kibana_1                           IycyuhuvTNaa6rfTLa7wGg   1   0       4681          932      3.4mb          3.4mb
green  open   .kibana_task_manager_1              dDyH2F6MTmuoCjDGX5dIsQ   1   0          7         4376    827.4kb        827.4kb
green  open   .logstash                           OfNrDsa6Sxm1zksRYGVxVg   1   0          1            0      5.7kb          5.7kb
green  open   .ml-config                          AR9cHZ1WSyukm4u59-2Mrw   1   0         30           11     95.3kb         95.3kb
green  open   .security-7                         QGY0cDP8Q2a_sXhFjBXkog   1   0         65            4    119.4kb        119.4kb
yellow open   .siem-signals-default-000001        D_e-1pDRQJqdmEFOJ_xihg   1   1         13            0    301.3kb        301.3kb
green  open   .tasks                              sRNizk3pSjqYFz3xfn9U9A   1   0          5            0     30.2kb         30.2kb
yellow open   apm-7.8.1-error-000001              sFDSKiKhSE2caRLNZDmROQ   1   1          3            0     77.9kb         77.9kb
yellow open   apm-7.8.1-metric-000001             EkvJD-7dRyKBaZI6oY5o9w   1   1    3065151            0    338.8mb        338.8mb
yellow open   apm-7.8.1-onboarding                q8D2Agy1QRKjb74kEk-EdA   1   1         10            0     64.9kb         64.9kb
yellow open   apm-7.8.1-profile-000001            qusHhO9dRGy_Qut67R2tnw   1   1          0            0       208b           208b
yellow open   apm-7.8.1-span-000001               pFWow77BSkSHliPEaqfvaw   1   1     476330            0    177.9mb        177.9mb
yellow open   apm-7.8.1-transaction-000001        2vkvvKnrRLm0jaenRX6Dpg   1   1     408425            0    126.5mb        126.5mb
yellow open   auditbeat-7.8.1-2020.11.11-000001   alFh9C_KTGKeaCvRqQJ9Nw   1   1    1534719            0    979.2mb        979.2mb
yellow open   filebeat-7.8.1-2020.11.11-000001    9kLspOJPSLGPlepwL4qCDA   1   1     959871            0    204.3mb        204.3mb
yellow open   forecast_example                    0VBZUtP6TtGQcsoj5rIGKQ   1   1       7488            0    579.3kb        579.3kb
yellow open   heartbeat-7.8.1-2020.11.11-000001   J6Zzop9ATWms-fFOBUBaZg   1   1    1382143            0    457.6mb        457.6mb
yellow open   journalbeat-7.8.1-2020.11.11-000001 IUApYtjfQOmfNNkcGR_bnQ   1   1     937567            0    247.4mb        247.4mb
yellow open   metricbeat-7.8.1-2020.11.11-000001  tjZX5pSIQtOfcpW6u-R65g   1   1   51472998            0      8.8gb          8.8gb
yellow open   packetbeat-7.8.1-2020.11.11-000001  U2huvZqkQQGGiB15bacEZg   1   1   11986554            0        5gb            5gb
yellow open   packetbeat-7.8.1-2020.11.17-000002  jqjDXaD0RFaVnx0u6vfG4w   1   1    7239852            0      2.7gb          2.7gb

_cat/indices/.ml-anomalies-*?v:

health status index                uuid                   pri rep docs.count docs.deleted store.size pri.store.size
green  open   .ml-anomalies-shared SzV0Lpo5RiWdUR2vAqRjRA   1   0      10112         1756      1.8mb          1.8mb

I remember I had something similar with heartbeat index as well some day

[droberts195 (David Roberts)]

It's because the .ml-anomalies* indices are now hidden indices. This prevents accidents like having an index template that applies to * apply the wrong mappings to indices used by internal features.

If you want _cat/indices to show hidden indices then add expand_wildcards=all or expand_wildcards=open,hidden to the call. Search for expand_wildcards in these docs to see all the options.