A MikroTik router with DNS feature enabled can be set as a DNS server
for any DNS-compliant client. Moreover, MikroTik router can be specified
as a primary DNS server under its dhcp-server settings. When the remote
requests are enabled, the MikroTik router responds to TCP and UDP DNS
requests on port 53.
DNS Cache Setup
- Submenu level: /ip dns
Description
DNS facility is used to provide domain name resolution for router itself as well as for the clients connected to it.Property Description
Property | Desciption |
---|---|
allow-remote-requests (yes | no; default: no) | specifies whether to allow network requests |
cache-max-ttl (time; default: 1w) | specifies maximum time-to-live for cache records. In other words, cache records will expire unconditionally after cache-max-ttl time. Shorter TTL received from DNS servers are respected |
cache-size (integer: 512..10240; default: 2048KiB) | specifies the size of DNS cache in KiB |
cache-used (read-only: integer) | displays the current cache size in KiB |
servers (IPv4/IPv6 address list; default: 0.0.0.0) | comma seperated list of DNS server IP addresses |
Note: Prior RouterOS v4.6 DNS servers in CLI was set up using fields primary-dns and secondary-dns starting from mentioned version these two fields are replaced with one field servers where all DNS server IP addresses should be listed
Note: If the property use-peer-dns under /ip dhcp-client is set to yes then primary-dns under /ip dns will change to a DNS address given by DHCP Server.
Example
To set 159.148.60.2 as the primary DNS server and allow the router to be used as a DNS server, do the following:[admin@MikroTik] ip dns> set servers=159.148.60.2 \ \... allow-remote-requests=yes [admin@MikroTik] ip dns> print servers: 159.148.60.2 allow-remote-requests: yes cache-size: 2048KiB cache-max-ttl: 1w cache-used: 7KiB [admin@MikroTik] ip dns>
Cache Monitoring
- Submenu level: /ip dns cache
Description
This menu provides a list with all address (DNS type "A") records stored on the serverProperty Description
Property | Desciption |
---|---|
address (read-only: IP address) | IP address of the host |
name (read-only: name) | DNS name of the host |
ttl (read-only: time) | remaining time-to-live for the record |
All DNS Entries
- Submenu level: /ip dns cache all
Description
This menu provides a complete list with all DNS records stored on the serverProperty Description
Property | Desciption |
---|---|
data (read-only: text) | DNS data field. IP address for type "A" records. Other record types may have different contents of the data field (like hostname or arbitrary text) |
name (read-only: name) | DNS name of the host |
ttl (read-only: time) | remaining time-to-live for the record |
type (read-only: text) | DNS record type |
Static DNS Entries
- Submenu level: /ip dns static
Description
The MikroTik RouterOS has an embedded DNS server feature in DNS cache. It allows you to link the particular domain names with the respective IP addresses and advertize these links to the DNS clients using the router as their DNS server. This feature can also be used to provide fake DNS information to your network clients. For example, resolving any DNS request for a certain set of domains (or for the whole Internet) to your own page.The server is capable of resolving DNS requests based on POSIX basic regular expressions, so that multiple requets can be matched with the same entry. In case an entry does not conform with DNS naming standards, it is considered a regular expression and marked with ‘R’ flag. The list is ordered and is checked from top to bottom. Regular expressions are checked first, then the plain records.
Property Description
Property | Desciption |
---|---|
address (IP address) | IP address to resolve domain name with |
name (text) | DNS name to be resolved to a given IP address. May be a regular expression |
ttl (time) | time-to-live of the DNS record |
Notes
Reverse DNS lookup (Address to Name) of the regular expression entries is not possible. You can, however, add an additional plain record with the same IP address and specify some name for it.Remember that the meaning of a dot (.) in regular expressions is any character, so the expression should be escaped properly. For example, if you need to match anything within example.com domain but not all the domains that just end with example.com, like www.another-example.com, use name=".*\\.example\\.com"
Regular expression matching is significantly slower than of the plain entries, so it is advised to minimize the number of regular expression rules and optimize the expressions themselves. Example
To add a static DNS entry for www.example.com to be resolved to 10.0.0.1 IP address:
[admin@MikroTik] ip dns static> add name www.example.com address=10.0.0.1 [admin@MikroTik] ip dns static> print Flags: D - dynamic, X - disabled, R - regexp # NAME ADDRESS TTL 0 www.example.com 10.0.0.1 1d [admin@MikroTik] ip dns static>
Flushing DNS cache
- Command name: /ip dns cache flush
Command Description
Command | Desciption |
---|---|
flush | clears internal DNS cache |
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