providers - Shorewall6 Providers file
This file is used to define additional routing tables. You will want to define
an additional table if:
•You have connections to more than one
ISP or multiple connections to the same ISP
•You run Squid as a transparent proxy
on a host other than the firewall.
•You have other requirements for policy
Each entry in the file defines a single routing table.
If you wish to omit a column entry but want to include an entry in the next
column, use "-" for the omitted entry.
The columns in the file are as follows.
The provider name. Must be a valid
shell variable name. The names 'local', 'main', 'default' and 'unspec' are
reserved and may not be used as provider names.
The provider number -- a number between 1 and
15. Each provider must be assigned a unique value.
(Optional) - value
A FWMARK value
used in your
(5) file to direct packets to this provider.
If HIGH_ROUTE_MARKS=Yes in shorewall6.conf
(5), then the value must be
a multiple of 256 between 256 and 65280 or their hexadecimal equivalents
(0x0100 and 0xff00 with the low-order byte of the value being zero).
Otherwise, the value must be between 1 and 255. Each provider must be assigned
a unique mark value. This column may be omitted if you don't use packet
marking to direct connections to a particular provider.
The name of an existing table to duplicate to
create this routing table. May be main or the name of a previously
listed provider. You may select only certain entries from the table to copy by
using the COPY column below.
The name of the network interface to the
provider. Must be listed in shorewall6-interfaces(5).
The IP address of the provider's gateway
You can enter detect
here and Shorewall6 will attempt to detect the
Beginning with Shorewall 5.0.6, you may also enter none
. This causes
creation of a routing table with no default route in it.
For PPP devices, you may omit this column.
(Optional) - [-
A comma-separated list selected from the
following. The order of the options is not significant but the list may
contain no embedded white-space.
Added in Shorewall 4.5.17. Causes a host route
to the provider's gateway router to be added to the provider's routing table.
This is the default behavior unless overridden by a following noautosrc
Added in Shorewall 4.4.25. The providers that
have balance specified will get outbound traffic load-balanced among
them. By default, all interfaces with balance specified will have the
same weight (1). Beginning with Shorewall 5.0.13, you can change the weight of
an interface by specifying balance=weight where weight is
the weight of the route out of this interface. Prior to Shorewall 5.0.13, only
one provider can specify this option.
Added in Shorewall 4.4.25. Indicates that a
default route through the provider should be added to the default routing
table (table 253). If a weight is given, a balanced route is added with
the weight of this provider equal to the specified weight. If the
option is given without a weight, an separate default route is added
through the provider's gateway; the route has a metric equal to the provider's
NUMBER. Prior to Shorewall 5.0.13, at most one provider can specify this
option and a weight may not be given.
If specified, inbound connections on this
interface are to be tracked so that responses may be routed back out this same
You want to specify track
if internet hosts will be connecting to local
servers through this provider.
Beginning with Shorewall 4.4.3, track
defaults to the setting of the
TRACK_PROVIDERS option in shorewall6.conf
 (5). If you set
TRACK_PROVIDERS=Yes and want to override that setting for an individual
provider, then specify notrack
Shorewall6 normally adds a routing rule for
each IP address on an interface which forces traffic whose source is that IP
address to be sent using the routing table for that interface. Setting
loose prevents creation of such rules on this interface.
Added in Shorewall 4.6.0. This option provides
an alternative method of load balancing based on probabilities. Providers to
be balanced are given a probability (a number 0 > n >= 1) with up
to 8 digits to the right of the decimal point. Beginning with Shorewall
4.6.10, a warning is issued if the sum of the probabilities is not
Added in Shorewall 4.5.17. Prevents the
addition of a host route to the provider's gateway router from being added to
the provider's routing table. This option must be used with caution as it can
cause start and restart failures.
Added in Shorewall 4.4.3. When specified,
turns off track.
(deprecated for use with providers that do not share an
If the interface named in the INTERFACE column
is not up and configured with an IPv4 address then ignore this provider. If
not specified, the value of the optional option for the INTERFACE in
shorewall6-interfaces(5) is assumed. Use of that option is preferred
to this one, unless an address is provider in the INTERFACE
Added in Shorewall 4.6.6, primary is a
synonym for balance (see above) and is preferred when the remaining
providers specify fallback or tproxy.
Specifies the source address to use when
routing to this provider and none is known (the local client has bound to the
0 address). May not be specified when an address is given in the
INTERFACE column. If this option is not used, Shorewall6 substitutes the
primary IP address on the interface named in the INTERFACE column.
Specifies the MTU when forwarding through this
provider. If not given, the MTU of the interface named in the INTERFACE column
Added in Shorewall 4.5.4. Used for supporting
the TPROXY action in shorewall-tcrules(5). See
http://www.shorewall.net/Shorewall_Squid_Usage.html. When specified,
the MARK, DUPLICATE and GATEWAY columns should be empty, INTERFACE should be
set to 'lo' and tproxy should be the only OPTION. Only one
tproxy provider is allowed.
Added in Shorewall 4.5.21. This is the default
behavior that results in a host route to the defined GATEWAY being
inserted into the main routing table and into the provider's routing table.
hostroute is required for older distributions but nohostroute
(below) is appropriate for recent distributions. hostroute may
interfere with Zebra's ability to add routes on some distributions such as
Added in Shorewall 4.5.21. nohostroute
inhibits addition of a host route to the defined GATEWAY being inserted
into the main routing table and into the provider's routing table.
nohostroute is not appropriate for older distributions but is
appropriate for recent distributions. nohostroute allows Zebra's to
correctly add routes on some distributions such as Debian 7.
Added in Shorewall 5.0.2 and alters the
behavior of the disable
•The provider's routing table still
contains the apprioriate default route.
•Unless the noautosrc option is
specified, routing rules are generated to route traffic from the interfaces
address(es) out of the provider's routing table.
•Persistent routing rules in
shorewall6-rtrules(5) are present.
The generated script will attempt to reenable a disabled persistent provider
during execution of the start
commands. When persistent
is not specified, only the enable
commands can reenable the provider.
A comma-separated list of other interfaces on
your firewall. Wildcards specified using an asterisk ("*") are
permitted (e.g., tun* ). Usually used only when DUPLICATE is main
copy routes through INTERFACE and through interfaces listed here. If you only
wish to copy routes through INTERFACE, enter none
in this column.
Beginning with Shorewall 4.5.17, blackhole, unreachable and prohibit routes are
no longer copied by default but may be copied by including
respectively in the
You run squid in your DMZ on IP address
2002:ce7c:92b4:1::2. Your DMZ interface is eth2
#NAME NUMBER MARK DUPLICATE INTERFACE GATEWAY OPTIONS
Squid 1 1 - eth2 2002:ce7c:92b4:1::2 -
eth0 connects to ISP 1. The ISP's gateway
router has IP address 2001:ce7c:92b4:1::2.
eth1 connects to ISP 2. The ISP's gateway router has IP address
eth2 connects to a local network.
#NAME NUMBER MARK DUPLICATE INTERFACE GATEWAY OPTIONS COPY
ISP1 1 1 main eth0 2001:ce7c:92b4:1::2 track eth2
ISP2 2 2 main eth1 2001:d64c:83c9:12::8b track eth2
shorewall6(8), shorewall6-accounting(5), shorewall6-actions(5),
shorewall6-blacklist(5), shorewall6-hosts(5), shorewall6-interfaces(5),
shorewall6-policy(5), shorewall6-rtrules(5), shorewall6-routestopped(5),
shorewall6-rules(5), shorewall6.conf(5), shorewall6-secmarks(5),
shorewall6-tcclasses(5), shorewall6-tcdevices(5), shorewall6-mangle(5),
shorewall6-tos(5), shorewall6-tunnels(5), shorewall6-zones(5)