12.6.5. Configuration of DNS

This section is located at the network dns level.

12.6.5.1. Settings for System DNS servers¶

You configure system DNS servers at the network dns system-dns-servers level.

To add new DNS servers or update the list of existing ones, use the following commands:

Admin@UGOS# set network dns system-dns-servers + [ <ip> <ip> ... ] 
Admin@UGOS# set network dns system-dns-servers [ <ip> <ip> ... ]

To delete the entire list of DNS server addresses, use the following command:

Admin@UGOS# delete network dns system-dns-servers

To delete individual servers, use the following command:

Admin@UGOS# delete network dns system-dns-servers [ <ip> <ip> ... ]

To display the list of system DNS servers, use the following command:

Admin@UGOS# show network dns system-dns-servers

You configure DNS proxies at the network dns proxy-settings level.

To update DNS proxy settings, use the following command:

Admin@UGOS# set network dns proxy-settings

Add the parameters you want to change:

Parameter	Description
filtering	DNS request filtering: on. off.
caching	Cache DNS responses: on. off.
limit	Limit the number of DNS queries per second for each user (default value: 100).
max-ttl	Maximum possible time-to-live for DNS records.
recursive	Perform recursive DNS queries: on. off.
dns-timeout	Time to the next attempt to query a DNS server (in milliseconds).
a-aaaa-unknown	Respond only to requests for A and AAAA records from unknown users. This effectively blocks attempts to establish a VPN over the DNS protocol: on. off.
retries	Number of attempts to send a DNS request.
factory-defaults	Reset the values of the selected parameter (parameters shown in this table) or all parameters (all) to factory defaults.

To display DNS proxy settings, use the following command:

Admin@UGOS# show network dns proxy-settings

The parameters you can view values for are listed in the table above.

You configure DNS rules at the network dns rules level using UPL. For more details on the command structure, see Configuring Rules Using UPL.

DNS rule parameters:

Parameter	Description
PASS OK	Action to create a rule using UPL.
enabled	Enable/disable the rule: enabled(yes) or enabled(true). enabled(no) or enabled(false).
name	The name of the rule. Example: name("DNS rule example").
desc	DNS proxy rule description. Example: desc("DNS rule example set via CLI").
url.domain	List of domains to which you want to redirect. You can use an asterisk () to specify a domain template. To specify a list of domains: url.domain = ".example.com"**.
dns_server	List of DNS server IP addresses to which requests for the specified domains should be forwarded. To specify a server: dns_server(1.2.3.4).

This section is located at the network dns static-records level.

To add a static DNS record, use the following command:

Admin@UGOS# create network dns static-records

Specify the parameters:

Parameter	Description
enabled	Enable/disable static record usage: on. off.
name	Record name.
description	DNS record description.
domain	Static record FQDN (Fully Qualified Name), e.g. www.example.com.
static-dns-ips	List of IP addresses the UserGate server will return when this FQDN is queried.

To update information about static DNS records, use the following command:

Admin@UGOS# set network dns static-records <static-record-name>

The set of parameters available to change is the same as those for the create command.

To delete a static record, use the following command:

Admin@UGOS# delete network dns static-records <static-record-name>

You can also delete only the static-dns-ips parameter values from the static record.

The following command:

Admin@UGOS# show network dns static-records

displays information about all existing static DNS records. To display information about a specific record, use the following command:

Admin@UGOS# show network dns static-records <static-record-name>