mta_sts_dns_cname_max_depth
Name
mta_sts_dns_cname_max_depth — specifies how many continuous CNAME lookups are allowed when doing DNS
lookups for MTA-STS TXT record for a domain. Exceeding the configured value will be treated as a DNS
lookup failure, which will be further treated as no MTA-STS policy available.
Synopsis
mta_sts_dns_cname_max_depth = 5
Description
Momentum supports MTA-STS policy delegation, which points the _mta-sts TXT record for the policy
domain via CNAME (to the _mta-sts record maintained by the provider). Momentum's DNS lookup
will follow the CNAMEs. To avoid a DNS lookup loop, Momentum uses this config option to limit how
many continuous CNAME lookups can happen before claiming a lookup failure.
The default value is 5.
Scope
mta_sts_dns_cname_max_depth is valid in the domain and global scopes.