Basic System Information¶
The TNSR CLI can set several basic elements about the system itself, which also
serves as a good introduction to making changes on TNSR. These settings are
These values are also propagated to SNMP, if configured. See Simple Network Management Protocol for information on setting up SNMP.
The following parameters are available:
- system contact <text>
System contact information, such as an e-mail address or telephone number (
- system description <text>
A brief description of this TNSR instance, for example its role or other identifying information (
- system location <text>
The location of this TNSR instance, for example a physical location such as a building name, room number, rack number/position, or VM host (
- system name <text>
The hostname of this TNSR instance (
This setting also changes the hostname in the host operating system to match, replacing any previously configured hostname.
This section of the CLI also contains a command which modifies the boot-time kernel command line parameters. That is an advanced task and as such it is covered in another section: Kernel Command Line Arguments.
This example shows how to set the above parameters, starting from basic mode:
gw tnsr# configure gw tnsr(config)# system contact email@example.com gw tnsr(config)# system description TNSR Lab Router gw tnsr(config)# system location HQ MDF/Rack 2 Top gw tnsr(config)# system name labrtr01 labrtr01 tnsr(config)# exit
To view the values of these parameters, along with uptime and memory usage, use
show system command from either basic or
labrtr01 tnsr# show system description: TNSR Lab Router contact: firstname.lastname@example.org name: labrtr01 location: HQ MDF/Rack 2 Top System Parameters: object-id: 220.127.116.11.4.1.13644 uptime: 1303615 seconds total-ram: 8004488 KiB free-ram: 3236820 KiB total-swap: 2932732 KiB free-swap: 2932732 KiB Platform: os-name: Linux os-release: 5.4.0-91-generic os-version: Ubuntu 20.04.3 LTS machine: x86_64 Product: product-vendor: Netgate product-name: TNSR product-model: x product-serial: 0
System DNS Resolution Behavior¶
The way TNSR and the host OS resolve hostnames via DNS can be fine-tuned if necessary. DNS resolution behavior has a separate configuration for each namespace (Networking Namespaces).
The default behavior in each namespace depends on the interface configuration. For example, if an interface is configured for DHCP, the DNS server supplied by the DHCP server will be used automatically.
DNS resolution behavior is configured using the
<namespace> command, which enters
config-dns-resolver mode. In that mode,
the following commands are available:
- server <name> <ip-addr>
Configures a DNS server IP address to be used as a forwarding DNS server in this namespace. This command may be repeated multiple times to configure multiple servers. The name parameter is for reference only.
- search <domain>
Configures a search domain, which is appended to hostnames without a domain name if a result is not found. This command may be repeated multiple times to configure multiple search domains.
DNS Resolution Examples¶
If Unbound is active and allows queries from
then the dataplane can be configured to use it as a DNS server:
tnsr(config)# system dns-resolver dataplane tnsr(config-dns-resolver)# server localhost 127.0.0.1 tnsr(config-dns-resolver)# exit
host namespace cannot access
unbound running in the
dataplane namespace, it must use a different external DNS server. Configure
the host operating system namespace to use specific forwarding DNS servers
directly as follows:
tnsr(config)# system dns-resolver host tnsr(config-dns-resolver)# server g1 18.104.22.168 tnsr(config-dns-resolver)# server g2 22.214.171.124 tnsr(config-dns-resolver)# exit