Magento – Magento 2 Reindex failed on customer grid

Magento 2 (Version 2.1.6) shows allways 2 or 3 Indexes with the processing state – and it never ends. It stays for days under processing.

After a php bin/magento indexer:reset all the indexes are out of date – which is fine I think.

But after a php bin/magento indexer:reindex I got the fallowing message:

php bin/magento indexer:reindex
Design Config Grid index has been rebuilt successfully in 00:00:00
Customer Grid indexer process unknown error:
SQLSTATE[42S02]: Base table or view not found: 1146 Table 'magento2.customer_grid_flat' doesn't exist, query was: CREATE TABLE IF NOT EXISTS customer_grid_flat (
entity_id int UNSIGNED NOT NULL COMMENT 'Entity ID' ,
name text NULL COMMENT 'Name' ,
email varchar(255) NULL COMMENT 'Email' ,
group_id int NULL COMMENT 'Group_id' ,
created_at timestamp NULL default NULL COMMENT 'Created_at' ,
website_id int NULL COMMENT 'Website_id' ,
confirmation varchar(255) NULL COMMENT 'Confirmation' ,
created_in text NULL COMMENT 'Created_in' ,
dob date NULL COMMENT 'Dob' ,
gender int NULL COMMENT 'Gender' ,
taxvat varchar(255) NULL COMMENT 'Taxvat' ,
lock_expires timestamp NULL default NULL COMMENT 'Lock_expires' ,
shipping_full text NULL COMMENT 'Shipping_full' ,
billing_full text NULL COMMENT 'Billing_full' ,
billing_firstname varchar(255) NULL COMMENT 'Billing_firstname' ,
billing_lastname varchar(255) NULL COMMENT 'Billing_lastname' ,
billing_telephone varchar(255) NULL COMMENT 'Billing_telephone' ,
billing_postcode varchar(255) NULL COMMENT 'Billing_postcode' ,
billing_country_id varchar(255) NULL COMMENT 'Billing_country_id' ,
billing_region varchar(255) NULL COMMENT 'Billing_region' ,
billing_street varchar(255) NULL COMMENT 'Billing_street' ,
billing_city varchar(255) NULL COMMENT 'Billing_city' ,
billing_fax varchar(255) NULL COMMENT 'Billing_fax' ,
billing_vat_id varchar(255) NULL COMMENT 'Billing_vat_id' ,
billing_company varchar(255) NULL COMMENT 'Billing_company' ,
PRIMARY KEY (entity_id),
INDEX CUSTOMER_GRID_FLAT_GROUP_ID (group_id),
INDEX CUSTOMER_GRID_FLAT_CREATED_AT (created_at),
INDEX CUSTOMER_GRID_FLAT_WEBSITE_ID (website_id),
INDEX CUSTOMER_GRID_FLAT_CONFIRMATION (confirmation),
INDEX CUSTOMER_GRID_FLAT_DOB (dob),
INDEX CUSTOMER_GRID_FLAT_GENDER (gender),
INDEX CUSTOMER_GRID_FLAT_BILLING_COUNTRY_ID (billing_country_id),
FULLTEXT FTI_8746F705702DD5F6D45B8C7CE7FE9F2F (name, email, created_in, taxvat, shipping_full, billing_full, billing_firstname, billing_lastname, billing_telephone, billing_postcode, billing_region, billing_city, billing_fax, billing_company)
) COMMENT='customer_grid_flat' ENGINE=INNODB charset=utf8 COLLATE=utf8_general_ci
Category Products index has been rebuilt successfully in 00:00:01
Product Categories index has been rebuilt successfully in 00:00:00
Product Price index has been rebuilt successfully in 00:00:00
Product EAV index has been rebuilt successfully in 00:00:03
Stock index has been rebuilt successfully in 00:00:00
Catalog Rule Product index has been rebuilt successfully in 00:00:00
Catalog Product Rule index has been rebuilt successfully in 00:00:00
Catalog Search index has been rebuilt successfully in 00:00:13
Search Spell-Correction index has been rebuilt successfully in 00:00:05
www-data@dicota-com:~/magento$
www-data@dicota-com:~/magento$
www-data@dicota-com:~/magento$ php bin/magento indexer:reindex
Design Config Grid index has been rebuilt successfully in 00:00:00
Customer Grid indexer process unknown error:
SQLSTATE[42S02]: Base table or view not found: 1146 Table 'magento2.customer_grid_flat' doesn't exist, query was: CREATE TABLE IF NOT EXISTS customer_grid_flat (
entity_id int UNSIGNED NOT NULL COMMENT 'Entity ID' ,
name text NULL COMMENT 'Name' ,
email varchar(255) NULL COMMENT 'Email' ,
group_id int NULL COMMENT 'Group_id' ,
created_at timestamp NULL default NULL COMMENT 'Created_at' ,
website_id int NULL COMMENT 'Website_id' ,
confirmation varchar(255) NULL COMMENT 'Confirmation' ,
created_in text NULL COMMENT 'Created_in' ,
dob date NULL COMMENT 'Dob' ,
gender int NULL COMMENT 'Gender' ,
taxvat varchar(255) NULL COMMENT 'Taxvat' ,
lock_expires timestamp NULL default NULL COMMENT 'Lock_expires' ,
shipping_full text NULL COMMENT 'Shipping_full' ,
billing_full text NULL COMMENT 'Billing_full' ,
billing_firstname varchar(255) NULL COMMENT 'Billing_firstname' ,
billing_lastname varchar(255) NULL COMMENT 'Billing_lastname' ,
billing_telephone varchar(255) NULL COMMENT 'Billing_telephone' ,
billing_postcode varchar(255) NULL COMMENT 'Billing_postcode' ,
billing_country_id varchar(255) NULL COMMENT 'Billing_country_id' ,
billing_region varchar(255) NULL COMMENT 'Billing_region' ,
billing_street varchar(255) NULL COMMENT 'Billing_street' ,
billing_city varchar(255) NULL COMMENT 'Billing_city' ,
billing_fax varchar(255) NULL COMMENT 'Billing_fax' ,
billing_vat_id varchar(255) NULL COMMENT 'Billing_vat_id' ,
billing_company varchar(255) NULL COMMENT 'Billing_company' ,
PRIMARY KEY (entity_id),
INDEX CUSTOMER_GRID_FLAT_GROUP_ID (group_id),
INDEX CUSTOMER_GRID_FLAT_CREATED_AT (created_at),
INDEX CUSTOMER_GRID_FLAT_WEBSITE_ID (website_id),
INDEX CUSTOMER_GRID_FLAT_CONFIRMATION (confirmation),
INDEX CUSTOMER_GRID_FLAT_DOB (dob),
INDEX CUSTOMER_GRID_FLAT_GENDER (gender),
INDEX CUSTOMER_GRID_FLAT_BILLING_COUNTRY_ID (billing_country_id),
FULLTEXT FTI_8746F705702DD5F6D45B8C7CE7FE9F2F (name, email, created_in, taxvat, shipping_full, billing_full, billing_firstname, billing_lastname, billing_telephone, billing_postcode, billing_region, billing_city, billing_fax, billing_company)
) COMMENT='customer_grid_flat' ENGINE=INNODB charset=utf8 COLLATE=utf8_general_ci
Category Products index has been rebuilt successfully in 00:00:02
Product Categories index has been rebuilt successfully in 00:00:00
Product Price index has been rebuilt successfully in 00:00:01
Product EAV index has been rebuilt successfully in 00:00:03
Stock index has been rebuilt successfully in 00:00:00
Catalog Rule Product index has been rebuilt successfully in 00:00:00
Catalog Product Rule index has been rebuilt successfully in 00:00:00
Catalog Search index has been rebuilt successfully in 00:00:11
Search Spell-Correction index has been rebuilt successfully in 00:00:05
`

I can repeat that – the same error message. I checked the database table and we have a magento2.customer_grid_flat – so it looks ok for me.
After a few days the index goes on status READY – without any interaction from our side. But then – 2 or 3 (mostly customer grid and catalog search) indexes are again the processing state and will not be updated longer (until we kill all indexes with the reset command)

Any hints?

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