mirror of
https://github.com/opnsense/docs
synced 2024-11-09 01:10:33 +00:00
130 lines
6.6 KiB
ReStructuredText
130 lines
6.6 KiB
ReStructuredText
=========
|
|
Gateways
|
|
=========
|
|
|
|
|
|
.. blockdiag::
|
|
:desctable:
|
|
|
|
blockdiag {
|
|
OPNsense [shape="cisco.firewall", label=""];
|
|
internet [shape="cloud"];
|
|
private_net [shape="cloud", label="private net"];
|
|
Gateway1 [shape="cisco.router", label=""];
|
|
Gateway2 [shape="cisco.router", label=""];
|
|
Gateway3 [shape="cisco.router", label=""];
|
|
OPNsense -> Gateway1 -> internet;
|
|
OPNsense -> Gateway2 -> internet [style = dotted];
|
|
OPNsense -> Gateway3 -> private_net;
|
|
|
|
}
|
|
|
|
|
|
Gateways define the possible routes that can be used to access other networks, such as the internet.
|
|
All different paths that are available to your firewall can be managed from this page, which can be found at :menuselection:`System->Gateways->Single`.
|
|
|
|
You can either define these gateways yourself, or they can be provided automatically from dynamical configured interfaces (e.g. dhcp), in which case they won't
|
|
have a predefined address.
|
|
|
|
When a gateway is generated automatically, you still have the ability to change its settings. Automatically generated gateways usually have
|
|
names like :code:`WAN_DHCP`.
|
|
|
|
In cases where you need to forward specific networks to a specific target, you can use static routes, which can be configured in
|
|
:menuselection:`System->Routes->Configuration` and depend on the entries shown in the gateway page.
|
|
|
|
A specific kind of route is the :code:`default` route, this is where all traffic is being send when no other static route is configured.
|
|
There can only be one default at a time per ip protocol (ipv4, ipv6) in the system routing table.
|
|
|
|
----------------------------
|
|
Default gateways
|
|
----------------------------
|
|
|
|
Since there can only be one active default gateway, we need a method to figure out which one to use.
|
|
For both ip protocols (ipv4, ipv6), this is determined equally.
|
|
|
|
Gateways have priorities, ranging from :code:`1` [very important] to :code:`255` [least important], automatically generated
|
|
gateways will receive a low priority by default (which you can change manually).
|
|
|
|
Next there is a setting called :code:`upstream`, which marks the gateway as favourable for default gateway selection, there can be more
|
|
than one upstream configured at the same time.
|
|
|
|
When choosing a default, the algorithm will always sort :code:`upstream` gateways higher (more attractive) and will use the priority next.
|
|
If none of the gateways is explicitly chosen as upstream, the first non upstream is chosen.
|
|
|
|
In cases where gateway monitoring is configured, choosing a gateway also involves testing its current status and act accordingly when the
|
|
monitored address is not reachable.
|
|
|
|
By default the system only chooses a (new) default gateway on startup or when an interface is connected or disconnected. In many cases
|
|
you might want the default gateway also changed when the current gateway is not reachable anymore (via configured monitoring), in which
|
|
case you can enable "Gateway switching" in :menuselection:`System->Settings->General`
|
|
|
|
.. Tip::
|
|
|
|
In case you have multiple (dynamic) gateways, which should fall over in a specific order on failure, just set a **priority** and **upstream** flag.
|
|
(e.g. favour fiber optics above 4g) Your choices should be reflected accordingly in the gateway grid (most important first).
|
|
|
|
|
|
----------------------------
|
|
Overview page
|
|
----------------------------
|
|
|
|
The overview page (:menuselection:`System->Gateways->Single`) shows all currently known gateways and their statuses in order of importance (most important on top).
|
|
When a gateway is considered "default" it will show **(active)** behind the name.
|
|
|
|
.. Note::
|
|
|
|
The **(active)** status shown in the list reflects the current calculated default, which might differ from the machine routing if gateway switching is not enabled.
|
|
You can always check the current active default in :menuselection:`System->Routes->Status`
|
|
|
|
.. Tip::
|
|
|
|
When debugging dynamic gateway issues, always check if your expected gateway is actually in the list. The system will only consider
|
|
items shown here.
|
|
|
|
----------------------
|
|
Settings
|
|
----------------------
|
|
|
|
Below you will find the most important settings that are available for a gateway item.
|
|
|
|
============================= =============================================================================
|
|
Disabled (temporary) disable this item
|
|
Name Unique name for this gateway
|
|
Description Optional description for this item
|
|
Interface The interface this gateway is connected to
|
|
Address Family IP family (v4 or v6)
|
|
IP address Address of our gateway, empty/**dynamic** when dynamically generated.
|
|
Upstream Gateway Upstream gateway, consider this gateway as default gateway candidate
|
|
Far Gateway Checkbox to allow the gateway to exist outside of the interface subnet.
|
|
Disable Gateway Monitoring Disable monitoring (consider **online**)
|
|
Monitor IP Alternative address to monitor, always make sure the address is
|
|
actually reachable and using this interface (via a static gateway)
|
|
Mark Gateway as Down Consider this gateway as down, so it can't be considered as default gateway
|
|
Priority Prioritizes this gateway, a lower value means more important.
|
|
============================= =============================================================================
|
|
|
|
|
|
---------------------------
|
|
Troubleshooting
|
|
---------------------------
|
|
|
|
Missing dynamic gateway
|
|
..........................
|
|
|
|
Most dynamic interface types write their current gateway into a file named :code:`/tmp/[interface]_router` or :code:`/tmp/[interface]_routerv6`.
|
|
When the expected gateway is not listed in the page, there might be an issue with the interface type (for example the remote server isn't providing one at the moment).
|
|
|
|
|
|
Gateway marked offline
|
|
.........................
|
|
|
|
When a gateway is marked offline, always check if the monitor address is reachable via the correct interface first.
|
|
You can use :menuselection:`Interfaces->Diagnostics->Ping` to test connectivity.
|
|
In case the monitor address is not in the same subnet as the interface,
|
|
also check if there's a static route (:menuselection:`System->Routes->Status`) available which sends the requested traffic to the correct upstream gateway.
|
|
|
|
There should always be a :code:`dpinger` process active, which you can check on the services page (:menuselection:`System->Diagnostics->Services`),
|
|
finally if all seems to be running you can deep dive into the packets leaving the interface,
|
|
if dpinger is active, there should be ICMP packets heading to your monitor address, which
|
|
you can inspect using :menuselection:`Interfaces->Diagnostics->Packet Capture`.
|