Why do I get a CNAME and MX record conflict prompt when adding a DNS resolution record?
Take example.com as an example.
|
MX | www | mx.mail.com |
CNAME | www | test.edgeone.com |
When performing a recursive resolution query, each record type has different priority, and CNAME has the highest priority. See RFC1034 and RFC2181. Therefore, during the resolution request process, the CNAME resolution record result will be returned first. When the host record value is the same, CNAME record and MX record cannot be configured at the same time, and you will get a prompt about the conflict.
If you do need to add CNAME and MX records at the same time when the host record is @, EdgeOne allows you to configure CNAME and records at the same time:
|
MX | @ | mx.mail.com |
CNAME | @ | test.edgeone.com |
Reminder:
This configuration will lead to unstable mailbox reception. If the Local DNS of the mailbox server prioritizes the resolution of the CNAME type of the @ record, the resolution of the MX type of the @ record will be affected, resulting in a resolution failure. If the host record is not @ , but the MX and CNAME records still indicate a conflict, please refer to the description of other record type conflicts below.
Why do I get a CNAME and TXT record conflict prompt when adding a DNS resolution record?
Take example.com as an example.
|
TXT | www | edgeone-txt-flag |
CNAME | www | test.edgeone.com |
The CNAME record has the highest priority, so if the host record is the same, configuring the CNAME record and the TXT record at the same time may cause the TXT record to fail to be resolved. In this case, EdgeOne will prompt record conflict.
If you do need to add CNAME and TXT records at the same time when the host record is @, EdgeOne allows you to configure CNAME and TXT records at the same time:
|
TXT | @ | edgeone-txt-flag |
CNAME | @ | test.edgeone.com |
Reminder:
This configuration will cause the TXT verification to fail, you can remove the CNAME record to solve this problem. TXT and CNAME records will still conflict when the host record is not @.
How do the record types conflict with one another?
See below for details:
✓: No conflict. When the HOST is the same, these two record types can both be configured. For example, after configuring the A record for www.example.com, you can still configure the MX record.
×: Conflict. When the HOST is the same, these two record types cannot be both configured. For example, after configuring the A record for www.example.com, you can not configure the CNAME record.
|
A | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
AAAA | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
CNAME | × | × | × | × | × | × | × | × |
MX | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
NS | × | × | × | × | ✓ | × | × | × |
TXT | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
SRV | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
CAA | ✓ | ✓ | × | ✓ | × | ✓ | ✓ | ✓ |
Note
The table above shows the conflict relationship when the HOST is not @. If the HOST is @, a CNAME record does not conflict with an MX or TXT record.
When the record type is A/AAAA/CNAME, can I configure both the resolution and acceleration when the HOST is the same?
Take the following configuration as an example:
In this case, if you want to enable acceleration for one record, there will be a conflict. To enable acceleration for 1.1.1.1, you need to delete 2.2.2.2 first.
Note
The above conflict happens on A/AAAA/CNAME records.
What happens if there are multiple A/AAAA/CNAME records with the same host record name and no weights are set?
If there are multiple A/AAAA records with the same host record name and no weights are set, all the A/AAAA records will be returned. If there are multiple CNAME records with the same host record name and no weights are set, one of the CNAME records will be returned using a round-robin method.
How long does it take for NS server configuration to take effect, and will it affect DNS record resolution?
After modifying the NS server address, due to caching by various ISPs, NS propagation typically takes 0-48 hours. The actual duration depends on domain registrars. Therefore, EdgeOne may not immediately detect the updated NS server address after modification. Please wait patiently.
Before the NS server changes take effect, DNS records will continue to resolve based on the configurations in the old NS server. To avoid service interruption during the transition, we strongly recommend ensuring all DNS records are imported into EdgeOne before switching. For import methods, refer to: Batch Import DNS Records. How long does it take for DNS record configurations to take effect?
After DNS record configuration, because local ISP DNS servers cache records, they will return cached resolution results to users until the cache expires, rather than requesting the latest records from NS servers. Actual resolution depends on the TTL expiration of cached records in ISP DNS servers. Propagation typically takes 5-30 minutes at fastest. If DNS server names were modified, it generally requires 24-48 hours to take effect.