Hallo,
danke für deine Antwort. Mir ist bewusst, dass ich den LDAP Teil nicht in der Konfig oben habe.
Ich scheitere bereits an folgendem:

Kopiere ich aus der Defaults.pm folgenden Abschnitt (Lokale Anmeldung) und füge diesen in die Config.pm ein, dann ist nichts mehr möglich. Im Browser wird dann nur noch Internal Server Error angezeigt.
Ich verstehe nicht ganz wieso das passiert. Immerhin ist es doch genau dasselbe, was in der Defaults.pm steht.

Der otobo-daemon-1 wird als unhealthy angezeigt. Im Log steht folgendes: Kernel::Config could not be loaded: at /opt/otobo/Kernel/System/ObjectManager.pm line 294.
Manage the OTOBO daemon process.

Ausschnitt:

# Data source 1: customer user database back end and settings.
$Self->{CustomerUser1} = {
Name   => ‚Database Backend‘,
Module => ‚Kernel::System::CustomerUser::DB‘,
Params => {
#            DSN => ‚DBI:odbc:yourdsn‘,
#            DSN => ‚DBI:mysql:database=customerdb;host=customerdbhost‘,
#            User => “,
#            Password => “,
Table => ‚customer_user‘,
SearchCaseSensitive => 0,
},

# customer unique id
CustomerKey => ‚login‘,

# customer #
CustomerID    => ‚customer_id‘,
CustomerValid => ‚valid_id‘,

# The last field must always be the email address so that a valid
#   email address like „John Doe“ <john.doe@domain.com> can be constructed from the fields.
CustomerUserListFields => [ ‚first_name‘, ‚last_name‘, ‚email‘ ],

#        CustomerUserListFields => [‚login‘, ‚first_name‘, ‚last_name‘, ‚customer_id‘, ‚email‘],
CustomerUserSearchFields           => [ ‚login‘, ‚first_name‘, ‚last_name‘, ‚customer_id‘ ],
CustomerUserSearchPrefix           => ‚*‘,
CustomerUserSearchSuffix           => ‚*‘,
CustomerUserSearchListLimit        => 250,
CustomerUserPostMasterSearchFields => [‚email‘],
CustomerUserNameFields             => [ ‚title‘, ‚first_name‘, ‚last_name‘ ],
CustomerUserEmailUniqCheck         => 1,

#        # Configures the character for joining customer user name parts. Join single space if it is not defined.
#        # CustomerUserNameFieldsJoin => “,

#        # show now own tickets in customer panel, CompanyTickets
#        CustomerUserExcludePrimaryCustomerID => 0,
#        # generate auto logins
#        AutoLoginCreation => 0,
#        # generate auto login prefix
#        AutoLoginCreationPrefix => ‚auto‘,
#        # admin can change customer preferences
#        AdminSetPreferences => 1,
# use customer company support (reference to company, See CustomerCompany settings)
CustomerCompanySupport => 1,
# cache time to live in sec. – cache any database queries
CacheTTL => 60 * 60 * 24,
#        # Consider this source read only.
#        ReadOnly => 1,
Map => [

# Info about dynamic fields:
#
# Dynamic Fields of type CustomerUser can be used within the mapping (see example below).
# The given storage (third column) then can also be used within the following configurations (see above):
# CustomerUserSearchFields, CustomerUserPostMasterSearchFields, CustomerUserListFields, CustomerUserNameFields
#
# Note that the columns ‚frontend‘ and ‚readonly‘ will be ignored for dynamic fields.

# note: Login, Email and CustomerID needed!
# var, frontend, storage, shown (1=always,2=lite), required, storage-type, http-link, readonly, http-link-target, link class(es)
[ ‚UserTitle‘,        Translatable(‚Title or salutation‘), ‚title‘,          1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserFirstname‘,    Translatable(‚Firstname‘),           ‚first_name‘,     1, 1, ‚var‘, “, 0, undef, undef ],
[ ‚UserLastname‘,     Translatable(‚Lastname‘),            ‚last_name‘,      1, 1, ‚var‘, “, 0, undef, undef ],
[ ‚UserLogin‘,        Translatable(‚Username‘),            ‚login‘,          1, 1, ‚var‘, “, 0, undef, undef ],
[ ‚UserPassword‘,     Translatable(‚Password‘),            ‚pw‘,             0, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserEmail‘,        Translatable(‚Email‘),               ‚email‘,          1, 1, ‚var‘, “, 0, undef, undef ],
#            [ ‚UserEmail‘,        Translatable(‚Email‘),               ‚email‘,          1, 1, ‚var‘, ‚[% Env(„CGIHandle“) %]?Action=AgentTicketCompose;ResponseID=1;TicketID=[% Data.TicketID | uri %];ArticleID=[% Data.ArticleID | uri %]‘, 0, “, ‚AsPopup OTOBOPopup_TicketAction‘ ],
[ ‚UserCustomerID‘,   Translatable(‚CustomerID‘),          ‚customer_id‘,    0, 1, ‚var‘, “, 0, undef, undef ],
#            [ ‚UserCustomerIDs‘,  Translatable(‚CustomerIDs‘),         ‚customer_ids‘,   1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserPhone‘,        Translatable(‚Phone‘),               ‚phone‘,          1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserFax‘,          Translatable(‚Fax‘),                 ‚fax‘,            1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserMobile‘,       Translatable(‚Mobile‘),              ‚mobile‘,         1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserStreet‘,       Translatable(‚Street‘),              ’street‘,         1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserZip‘,          Translatable(‚Zip‘),                 ‚zip‘,            1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserCity‘,         Translatable(‚City‘),                ‚city‘,           1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserCountry‘,      Translatable(‚Country‘),             ‚country‘,        1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚UserComment‘,      Translatable(‚Comment‘),             ‚comments‘,       1, 0, ‚var‘, “, 0, undef, undef ],
[ ‚ValidID‘,          Translatable(‚Valid‘),               ‚valid_id‘,       0, 1, ‚int‘, “, 0, undef, undef ],

# Dynamic field example
#            [ ‚DynamicField_Name_X‘, undef, ‚Name_X‘, 0, 0, ‚dynamic_field‘, undef, 0, undef, undef ],
],

# default selections
Selections => {

#            UserTitle => {
#                ‚Mr.‘ => Translatable(‚Mr.‘),
#                ‚Mrs.‘ => Translatable(‚Mrs.‘),
#            },
},
};

Hallo Marcel,

Gerne. Das würde mir sicher weiterhelfen.