Improve client troubleshooting docs (#286)

* improve client troubleshooting docs

* feat: add information on verifying system's routing rules

* chore: unify terms used

* feat: add Can a routing peer `peer-b` forward traffic to `srv-c`?
This commit is contained in:
Krzysztof Nazarewski (kdn)
2025-03-13 16:27:10 +01:00
committed by GitHub
parent 956a948b99
commit 60718cfae0

View File

@@ -1,13 +1,17 @@
# Troubleshooting client issues
This document offers practical tips and insights to help you debug various problems, ensuring a seamless user experience.
This document offers practical tips and insights to help you debug various problems, ensuring a seamless user
experience.
## NetBird agent status
The netbird agent is a daemon service that runs in the background; it provides information about peers connected and about the NetBird control services. You can check the status of the agent with the following command:
The netbird agent is a daemon service that runs in the background; it provides information about peers connected and
about the NetBird control services. You can check the status of the agent with the following command:
```shell
netbird status --detail
````
This will output the following information:
```shell
@@ -61,29 +65,42 @@ Quantum resistance: false
Routes: -
Peers count: 2/2 Connected
```
As you can see, the output shows the peers connected, the NetBird IP address, the public key, the connection status, and the connection type.
The status will also report if there is an issue connecting to the relay servers, the management server, or the signal server.
As you can see, the output shows the peers connected, the NetBird IP address, the public key, the connection status, and
the connection type. The status will also report if there is an issue connecting to the relay servers,
the management server, or the signal server.
As for Peers, the status will show the following information:
* `Connection type`: P2P, Relayed, where relayed connections indicate a limitation in the network that prevents a direct connection between the peers.
* `Direct`: true/false, where true indicates a direct connection between the peers without a local proxy. This case is common when the local peer is allocating the relay connection.
* `ICE candidate (Local/Remote)`: relay/host, where relay indicates that the local peer is using a relay connection and host indicates that the remote peer is using a direct connection.
* `Last Wireguard handshake`: Indicating the last time the Wireguard handshake was performed. Usually, this is performed every 2 minutes, and if you don't see an update here or if the value is empty, that indicates that the connection wasn't possible yet.
* `Transfer status (received/sent)`: Indicating the amount of data received and sent by the peer. This is useful to check if the connection is being used.
* `Connection type`: P2P, Relayed, where relayed connections indicate a limitation in the network that prevents a direct
connection between the peers.
* `Direct`: true/false, where true indicates a direct connection between the peers without a local proxy. This case is
common when the local peer is allocating the relay connection.
* `ICE candidate (Local/Remote)`: relay/host, where relay indicates that the local peer is using a relay connection and
host indicates that the remote peer is using a direct connection.
* `Last Wireguard handshake`: Indicating the last time the Wireguard handshake was performed. Usually, this is performed
every 2 minutes, and if you don't see an update here or if the value is empty, that indicates that the connection
wasn't possible yet.
* `Transfer status (received/sent)`: Indicating the amount of data received and sent by the peer. This is useful to
check if the connection is being used.
See more details about the status command [here](/how-to/cli#status).
## Getting client logs
By default, client logs are located in the `/var/log/netbird/client.log` file on macOS and Linux and in the `C:\ProgramData\netbird\client.log` file on Windows.
You can analyze the logs to identify the root cause of the problem. If you need help, open a [github issue](https://github.com/netbirdio/netbird/issues/new/choose) and attach the logs.
By default, client logs are located in the `/var/log/netbird/client.log` file on macOS and Linux and in the
`C:\ProgramData\netbird\client.log` file on Windows.
You can analyze the logs to identify the root cause of the problem. If you need help, open
a [github issue](https://github.com/netbirdio/netbird/issues/new/choose) and attach the logs.
### Debug bundle
A debug archive containing the recent logs and the status at the time of execution can be generated with the following command.
A debug archive containing the recent logs and the status at the time of execution can be generated with the following
command.
Adding the `-A` flag will anonymize the logs, removing sensitive information such as public IP addresses and domain names.
Adding the `-S` flag will add system information like network routes and interfaces
Adding the `-A` flag will anonymize the logs, removing sensitive information such as public IP addresses and domain
names. Adding the `-S` flag will add system information like network routes and interfaces
```shell
netbird debug bundle -AS
@@ -93,17 +110,17 @@ This will output the path of the generated file, which can be accessed with admi
### Debug for a specific time
To capture logs for a specific time period, you can use the `debug for` command. This will generate a debug bundle after the specified time has elapsed.
To capture logs for a specific time period, you can use the `debug for` command. This will generate a debug bundle after
the specified time has elapsed.
```shell
netbird debug for 5m -AS
```
To capture any issues arising during the `up` and `down` processes, this will set the log level to `TRACE` and bring netbird `up` and `down` up to a few times.
To capture any issues arising during the `up` and `down` processes, this will set the log level to `TRACE` and bring
netbird `up` and `down` up to a few times.
After 5 minutes the netbird status will be restored to the previous state and the debug bundle will be generated.
## Enabling debug logs on agent
Logs can be temporarily set using the following command.
@@ -125,6 +142,7 @@ Using `netbird down` and `netbird up` will not reset the log level.
To permanently set the log level, see the following sections.
### On Linux with systemd
The default systemd unit file reads a set of environment variables from the path `/etc/sysconfig/netbird`.
You can add the following line to the file to enable debug logs:
@@ -135,6 +153,7 @@ sudo systemctl restart netbird
```
### On Other Linux and MacOS
```shell
sudo netbird service stop
sudo netbird service uninstall
@@ -143,7 +162,8 @@ sudo netbird service start
```
### On Windows
You need to run the following commands with an elevated Powershell window.
You need to run the following commands with an elevated PowerShell or `cmd.exe` window.
```shell
netbird service stop
@@ -153,6 +173,7 @@ netbird service start
```
### On Docker
You can set the environment variable `NB_LOG_LEVEL` to `debug` to enable debug logs.
```shell
@@ -161,51 +182,65 @@ docker run --rm --name PEER_NAME --hostname PEER_NAME --cap-add=NET_ADMIN --cap-
```
### On Android
Enable the ADB in the developer menu on the Android device.
Enable the ADB in the developer menu on the Android device.
In the app set the the Trace log level setting - it is a checkbox in the advanced menu.
With the ADB tool, you can get the logs from your device. The ADB is part of the SDK platform tools pack (zip file).
You can download it from [here](https://developer.android.com/tools/releases/platform-tools).
Please extract it and run the next command in the case of Linux:
With the ADB tool, you can get the logs from your device. The ADB is part of the SDK platform tools pack (zip file).
You can download it from [here](https://developer.android.com/tools/releases/platform-tools).
Please extract it and run the next command in the case of Linux:
```shell
sudo adb logcat -v time | grep GoLog
```
## Running the agent in foreground mode
You can run the agent in foreground mode to see the logs in the terminal. This is useful to debugging issues with the agent.
You can run the agent in foreground mode to see the logs in the terminal. This is useful to debugging issues with the
agent.
### Linux and MacOS
```shell
sudo netbird service stop
sudo netbird up -F
```
### Windows
On Windows, the agent depends on the Wireguard's `wintun.dll` and can only be executed as a system account.
To run the agent in foreground mode, you need to use a tool called [PSExec](https://learn.microsoft.com/en-us/sysinternals/downloads/psexec).
To run the agent in foreground mode, you need to use a tool
called [PSExec](https://learn.microsoft.com/en-us/sysinternals/downloads/psexec).
Once you have downloaded and extracted `psexec` open an elevated Powershell window:
```shell
netbird service stop
.\PsExec64.exe -s cmd.exe /c "netbird up -F --log-level debug > c:\windows\temp\netbird.out.log 2>&1"
```
In case you need to configure environment variables, you need to add them as system variables so they get picked up by the agent on the next psexec run:
In case you need to configure environment variables, you need to add them as system variables so they get picked up by
the agent on the next psexec run:
```shell
[Environment]::SetEnvironmentVariable("PIONS_LOG_DEBUG", "all", "Machine")
````
## Enabling WireGuard in user space
Sometimes, you want to test NetBird running on userspace mode instead of a kernel module. That can be a check to see if there is a problem with NetBird's firewall management in kernel mode.
Sometimes, you want to test NetBird running on userspace mode instead of a kernel module. That can be a check to see if
there is a problem with NetBird's firewall management in kernel mode.
You must run the agent in foreground mode and set the environment variable `NB_WG_KERNEL_DISABLED` to `true`.
```shell
sudo netbird service stop
sudo bash -c 'NB_WG_KERNEL_DISABLED=true netbird up -F' > /tmp/netbird.log
```
## Debugging GRPC
## Debugging GRPC
The NetBird agent communicates with the Management and Signal servers using the GRPC framework. With these parameters, you can
The NetBird agent communicates with the Management and Signal servers using the GRPC framework. With these parameters,
you can
set verbose logging for this service.
```shell
@@ -215,8 +250,10 @@ sudo bash -c 'GRPC_GO_LOG_VERBOSITY_LEVEL=99 GRPC_GO_LOG_SEVERITY_LEVEL=info net
## Debugging ICE connections
The Netbird agent communicates with other peers through the Interactive Connectivity Establishment (ICE) protocol described in the [RFC 8445](https://datatracker.ietf.org/doc/html/rfc8445). To debug the connection procedure,
set verbose logging for the the [Pion/ICE](https://github.com/pion/ice) library with the `PIONS_LOG_DEBUG` or `PIONS_LOG_TRACE` variable.
The Netbird agent communicates with other peers through the Interactive Connectivity Establishment (ICE) protocol
described in the [RFC 8445](https://datatracker.ietf.org/doc/html/rfc8445). To debug the connection procedure,
set verbose logging for the the [Pion/ICE](https://github.com/pion/ice) library with the `PIONS_LOG_DEBUG` or
`PIONS_LOG_TRACE` variable.
```shell {{ title: 'Environment variable' }}
PIONS_LOG_DEBUG=all
@@ -227,3 +264,422 @@ NB_LOG_LEVEL=debug
sudo netbird service stop
sudo bash -c 'PIONS_LOG_DEBUG=all NB_LOG_LEVEL=debug netbird up -F' > /tmp/netbird.log
```
## Debugging access to network resources
In this section we will be presenting methodology of troubleshooting access issues involving Netbird.
We will start by presenting a glossary of all machines and services involved.
A sub-section will describe a specific use case.
Each will start with a concise summary of usual troubleshooting steps then expand into more detailed step-by-step
guides.
### Glossary
We will be using the following names for resources outside the Netbird network:
- `int-net1`: an internal network `10.123.45.0/24`,
- `srv-c`: an internal HTTP server running at `10.123.45.17`,
- `int-dns1`: an internal DNS server running at `10.123.45.6`,
- `int-dns2`: an internal DNS server nunning at `10.7.8.9`,
- `cf-dns`: an Internet-accessible CloudFlare DNS server at `1.1.1.1` and `1.0.0.1`,
and following Netbird network resources:
- `peer-a`: end user's device running Netbird Client,
- `peer-b`: a linux server inside the internal network running Netbird Client,
- it has direct access to the whole `int-net1` IP range,
- `users:employees`: a Netbird Group containing `peer-a`,
- `routers:int-net1`: a Netbird Group containing `peer-b`,
- `access:srv-c`: a Netbird Groups used as a target of ACL rules for `srv-c` only,
- `access:int-net1`: a Netbird Groups used as a target of ACL rules for the whole subnet,
- `net-a`: a Netbird Network
- `net-a:srv-c`: a Network Resource handling traffic to `10.123.45.17/32` (`srv-c`),
- `net-a:int-net1`: a Network Resource handling traffic to `10.123.45.0/24` (`int-net1`),
- `route:int-net1`: a Netbird Network Route handling traffic to `10.123.45.0/24` (`int-net1`),
- `route:srv-c`: a Netbird Network Route handling traffic to `10.123.45.17/32` (`srv-c`),
### Access from `peer-a` to `srv-c`
In short:
1. Does `peer-b` have direct access to `srv-c`'s port `80`?
2. Can a routing peer `peer-b` forward traffic to `srv-c`?
3. Are Netbird's network routing resources configured?
4. Do Netbird's Access Control rules allow access from `peer-a` to `peer-b`?
5. Do Netbird's Access Control rules allow access from `peer-a` to the target's ACL Group?
6. Is `peer-a`'s operating system configured to use the route?
#### Does `peer-b` have direct access to `srv-c`'s port `80`?
After logging in to `peer-b` you can confirm/troubleshoot the HTTP port `80` connection by issuing any of the following
commands:
```shell
curl -v "http://10.123.45.17"
curl --fail -v --max-time=2 "http://10.123.45.17:80"
wget -O - --timeout=2 "http://10.123.45.17:80"
nc -nvz -w 2 10.123.45.17 80
```
You can also try `ping` (an ICMP packet), but the firewall might have a different configuration for ICMP and TCP ports:
```shell
ping --numeric --count=1 --timeout=2 10.123.45.17
```
#### Can a routing peer `peer-b` forward traffic to `srv-c`?
<Note>
Only Linux OS machines can be assigned as routing peers.
</Note>
This is more complicated to test, but usually boils down to confirming `net.ipv4.ip_forward` is set to `1` on `peer-b`'s
Linux operating system:
```shell
> sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1
```
For setting up the value persistently (across reboots) please consult your operating system's documentation.
It is often handled by either `/etc/sysctl.conf` or `/etc/sysctl.d/*.conf` files.
Testing the functionality in practice involves:
- connecting to another machine with direct access to `peer-b`,
- adding a routing table entry to route `int-net1` (`10.123.45.0/24`) traffic through it,
- trying to at least `ping 10.123.45.17` (`srv-c`)
#### Are Netbird's network routing resources configured?
For Netbird network routing resources configurations you can use either (new) _Networks_ or (old) _Network Routes_.
A Network `net-a` should have at minimum:
- _Network Resource_: `net-a:srv-c` with either of:
- an _Address_ set to `10.123.45.17/32` to configure route to `srv-c` exclusively and nothing else,
- _Assigned Groups_ set to `access:srv-c`
- _Routing Peer Group_ assigned to `routers:int-net1`
A _Network Route_ `route:srv-c` should have at least:
- a _Network Range_ set to `10.123.45.17/32` to configure route to `srv-c` exclusively and nothing else,
- _Routing Peer Group_ assigned to `routers:int-net1`,
- _Distribution Group_ assigned to `users:employees`,
- (optional) _Access Control Groups_ assigned to `access:srv-c`,
You can loosen the rules and replace following to grant access to the whole `int-net1` network range:
- _Address_: `10.123.45.17/32` -> `10.123.45.0/24`,
- _Assigned Groups_ / _Access Control Groups_: `access:srv-c` -> `access:int-net1`
#### Do Netbird's Access Control rules allow access from `peer-a` to `peer-b`?
There should be an _Access Control Policy_ present allowing traffic from `users:employees` Group to `routers:int-net1`
Group.
You can confirm the _Policy_ is working by:
1. logging in to `peer-a`,
2. issuing `netbird status -d` command,
3. finding `peer-b.netbird.cloud` under `Peers detail`,
In the most specific setup it should have at:
- have `TCP` protocol selected,
- a blue arrow should point from left to right and a second right-to-left arrow should be greyed out,
- a _Source group_ set to `users:employees`,
- a _Destination group_ set to `routers:int-net1`,
- have `80` in the Ports section,
You can loosen above example by:
- allowing `ALL` protocol, _Ports_ will become greyed out because all traffic will be allowed,
- creating a bidirectional rule (both arrows should be green), always true for the protocol `ALL`,
- selecting a different source group from the pool assigned to `peer-a`,
- it could be built-in `All` group, but it is discouraged,
- selecting a different destination group from the pool assigned to `peer-b`,
- it could be built-in `All` group, but it is discouraged,
#### Do Netbird's Access Control rules allow access from `peer-a` to the target's ACL Group?
You can skip this check, when you are using (old) Network Route feature without filling in _Access Control Groups (
optional)_ section.
Otherwise, there should be an _Access Control Policy_ present allowing traffic from one of `peer-a`'s Groups to:
- _Networks Resource_'s _Assigned Groups_: `access:srv-c` or `access:int-net1`,
- _Network Route_'s _Access Control Groups_: `access:srv-c` or `access:int-net1`,
You can confirm the _Policy_ is working by:
1. logging in to `peer-a`,
2. issuing `netbird status -d` command,
3. finding `peer-b.netbird.cloud` under `Peers detail`,
4. finding `10.123.45.0/24` or `10.123.45.17/32` under `peer-b.netbird.cloud`'s _Networks_ field,
In the most specific setup it should have at:
- have `TCP` protocol selected,
- a blue arrow should point from left to right and a second right-to-left arrow should be greyed out,
- a _Source group_ set to `users:employees`,
- a _Destination group_ set to `access:srv-c`,
- have `80` in the Ports section,
Just like with the previous section you can loosen the above example by:
- replacing `access:srv-c` _Group_ with `access:int-net1` _Group_,
- allowing `ALL` protocol, _Ports_ will become greyed out because all traffic will be allowed,
- creating a bidirectional rule (both arrows should be green), always true for the protocol `ALL`,
- selecting a different source group from the pool assigned to `peer-a`,
- it could be built-in `All` group, but it is discouraged,
- selecting a different destination group from the pool assigned to `peer-b`,
- it could be built-in `All` group, but it is discouraged,
#### Is `peer-a`'s operating system configured to use the route?
After all resources are configured in the Netbird management you should check whether they are
properly registered with your operating system.
You can start by checking Netbird client's configuration with `netbird status -d` command:
```shell
% netbird status -d
Peers detail:
brys-vm-nbt-ubuntu-isolated-01.netbird.cloud:
...
Status: Connected
-- detail --
Connection type: P2P
...
Networks: 10.123.45.0/24
...
Peers count: 1/1 Connected
```
You should be primarily looking for _Networks_ section under each _Peers detail_, but you can also check:
- _Peer_'s name,
- _Peer_'s _Status_: it should be `Connected`,
- _Peer_'s _Connection type_: it can be either `P2P` (direct) or `Relayed` (over the Internet),
- _Peers count_ near the end of the output,
##### Verifying routing configuration on the Windows operating system
Below commands assume running a PowerShell prompt with administrator's privileges.
The easiest way is to read output of `Get-NetRoute` command:
```shell
PS C:\Users\user> Get-NetRoute
ifIndex DestinationPrefix NextHop RouteMetric ifMetric PolicyStore
------- ----------------- ------- ----------- -------- -----------
...
17 10.123.45.255/32 0.0.0.0 256 5 ActiveStore
17 10.123.45.0/24 0.0.0.0 1 5 ActiveStore
...
17 100.83.255.255/32 0.0.0.0 256 5 ActiveStore
17 100.83.183.133/32 0.0.0.0 256 5 ActiveStore
17 100.83.0.0/16 0.0.0.0 256 5 ActiveStore
...
```
You should be looking for your specific subnet's IP ranges (`10.123.45.0/24` in case of `int-net1`) and anything from
`100.*.0.0/16` range.
Some other alternatives are `route print` & `Get-NetIPConfiguration`.
##### Verifying routing configuration on the MacOS operating system
The easiest way to verify system configuration is `netstat -nr` command:
```shell
% netstat -nr
Routing tables
Internet:
Destination Gateway Flags Netif Expire
...
100.83/16 utun100 USc utun100
100.83.19.63 100.83.19.63 UH utun100
...
10.123.45 utun100 USc utun100
...
Internet6:
Destination Gateway Flags Netif Expire
...
```
You should be looking for `utun*` interface in 4th column and searching the rows for
your specific subnet's clamped IP ranges (`10.123.45` in case of `int-net1`) and anything from `100.*/16` range.
##### Verifying routing configuration on the Linux operating system
Depending on specifics of your Linux distribution (or even your configuration of it) you should be able to use either
`iproute2` or `net-tools` family of network commands.
Netbird client stores it's custom routes in the routing table `7120` (or `0x1BD0`) when it's available (through
`iproute2` interface).
For `iproute2` (`ip`, `ss` tools):
- `ip route` to find built-in `100.*.0.0/16` route,
- `ip route show table 7120` or `ip route show table all` to find the specific routed networks,
For `net-tools` (`ifconfig`, `route`, `netstat` tools):
- `route -n` to find built-in `100.*.0.0/16` route,
- neither `route` nor `netstat` support viewing content of custom routing tables,
### Public nameservers
When you configure a _Nameserver_ accessible from the Internet without a VPN, the Netbird client acts as a proxy
to the public nameserver.
There are really just two things you can check:
1. Confirm Netbird client picked up the nameserver,
2. Confirm the operating system is configured to use Netbird client's proxy nameserver,
You can check the first one in operating system independent manner by:
1. running `netbird status -d`,
2. locating the _Nameserver_'s IP address
3. confirming it _is Available_ (it could also be timed out or in other state)
```
...
Nameservers:
[1.1.1.1:53, 1.0.0.1:53] for [.] is Available
...
```
#### Verifying the DNS names resolve properly in practice
Here is a short summary of commands querying nameservers for `name.at.example.com` in different operating systems.
The `.` at the end makes sure you are querying a fully-qualified names independent of your local network's configuration
(specifically search domains):
```shell
# MacOS
dscacheutil -q host -a name name.at.example.com.
# Windows PowerShell
Resolve-DnsName -Name name.at.example.com.
# Linux/UNIX
dig name.at.example.com.
nslookup name.at.example.com.
# Linux with systemd-resolved
resolvectl query name.at.example.com.
```
#### Verifying the nameservers are properly registered in Windows operating system
To confirm the nameservers are properly registered in Windows operating system using PowerShell:
```shell
PS C:\Users\user> Get-DnsClientNrptRule
Name : NetBird-Match
Version : 2
Namespace : {.netbird.cloud, .83.100.in-addr.arpa}
...
NameServers : 100.83.255.254
...
PS C:\Users\kdn> Get-DnsClientNrptPolicy
Namespace : .83.100.in-addr.arpa
...
NameServers : 100.83.255.254
..
Namespace : .netbird.cloud
...
NameServers : 100.83.255.254
...
```
You should be searching for following in the outputs of above commands:
- the `100.XXX.255.254` under _Nameservers_ (a local proxy address of the Netbird client)
- `.netbird.cloud` and `.XXX.100.in-addr.arpa` under matching _Namespace_ for built-in entries,
- `.your.custom.domain.example.com` under matching _Namespace_ for your custom domains,
#### Verifying the nameservers are properly registered in MacOS operating system
To confirm the nameservers are properly registered in MacOS operating system using terminal:
```shell
> scutil --dns
...
resolver #2
domain : netbird.cloud
nameserver[0] : 100.83.255.254
port : 53
flags : Supplemental, Request A records, Request AAAA records
reach : 0x00000002 (Reachable)
order : 101200
...
resolver #8
domain : 83.100.in-addr.arpa
nameserver[0] : 100.83.255.254
port : 53
flags : Supplemental, Request A records, Request AAAA records
reach : 0x00000002 (Reachable)
order : 102402
...
```
You should be searching for following in the outputs of above commands:
- the `100.XXX.255.254` under _nameserver[N]_ (a local proxy address of the Netbird client)
- `netbird.cloud` and `.XXX.100.in-addr.arpa` under matching _domain_ for built-in entries,
- `.your.custom.domain.example.com` under matching _domain_ for your custom domains,
- `Reachable` under `reach` field,
#### Verifying the nameservers are properly registered in Linux operating system
Nameserver can be configured in different ways depending on your specific distribution's configuration:
For `systemd-resolved`, you can see the config with `resolvectl status`,
For other configuration backends, you should see additional entries in `/etc/resolv.conf`:
- `127.0.0.1` - default address for Netbird DNS proxy listener
- `127.0.0.153` - fallback address for Netbird DNS proxy listener
- value of `$NB_DNS_RESOLVER_ADDRESS` - a custom override for the Netbird DNS proxy listener
You can find the address Netbird client is listening by issuing one of following commands:
```shell
sudo ss -nlptu 'sport = 53' | grep netbird
sudo netstat -ltnup | grep ':53' | grep netbird
```
### Internal nameservers
When you configure an internal _Nameserver_, not accessible from the Internet in addition to steps
described in the previous section _Public nameservers_
you should make sure the _Nameserver_'s IP addresses are properly routed and accessible.
Please refer to _Access from `peer-a` to `srv-c`_ section above.
To configure `int-dns1`, while following _Access from `peer-a` to `srv-c`_ section you should:
- substitute port `80` for port `53`
- substitute ip address `10.123.45.17` for `10.123.45.6`,
To configure `int-dns2`, while following _Access from `peer-a` to `srv-c`_ section you should:
- substitute port `80` for port `53`
- completely ignore the `10.123.45.0/24` network instructions,
- substitute ip address `10.123.45.17` for `10.7.8.9`,
- create a respective _Network_ (along with _Resources_ and _Routing Peers_) or _Network Route_ for the `10.7.8.9/32` IP
address range,
To test the configuration in practice please refer to previous section _Public nameservers_.
usb-storage,drive=raw-30F4989D-AE95B60F797D,serial=30F4989D-AE95B60F797D