I have a DNS setup with IBM SOFTLAYER with below setup
$ORIGIN mydomain.com.
$TTL 86400
@ IN SOA ns1.softlayer.com. support.softlayer.com. (
2018110900 ; Serial
7200 ; Refresh
600 ; Retry
1728000 ; Expire
43200) ; Minimum
@ 86400 IN NS ns1.softlayer.com.
@ 86400 IN NS ns2.softlayer.com.
@ 60 IN TXT v=spf1 include:_spf.google.com ~all
google._domainkey 86400 IN TXT v=DKIM1; k=rsa; p=AB
_dmarc.mydomain.com. 86400 IN TXT v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected]
* 900 IN CNAME mydomain.com.
devadmin 86400 IN CNAME admin.mydomain.com.
ftp 86400 IN CNAME admin.mydomain.com.
@ 86400 IN A 100.100.100.100
admin 86400 IN A 200.200.200.200
This setup works fine and I can resolve queries like mydomain.com, devmedia.mydomain.com, x.devmedia.mydomain.com
The issue arises when I add another TXT record for Lets Encrypt domain validation.
_acme-challenge.devmedia 60 IN TXT txttestrest
Once added, domains with devmedia.mydomain.com stop resolving.
Is this normal behavior or some bug in DNS.
Do I need to add devmedia.mydomain.com explicitly in my DNS or there is some other way to do this.
CNAME records are not allowed to co-exist with other records. Since you have a CNAME defined for devmedia, you can't create a acme-challenge.devmedia. So either you need to change devmedia to an A record, or handle it some other way.
It might work to create acme-challenge.admin instead, since that is where the CNAME points, but I am not sure if they will actually check that way.