Digi TransPort WR31 User Manual page 711

Configure security settings
Using [inspect-state] with the Out Of Service option
You can use the inspect-state field with an optional oos parameter. This parameter allows the
stateful inspect engine to mark as out of service any routes that are associated with the specified
interface and also to control how and the interfaces are returned to service. Such routes will only be
marked as out of service if the specified oos option parameters are met. The oos parameter takes
the format:
oos {interface-name¦logical-name} secs {t=secs} {c=count} {d=count}
{r="ping"|"tcp"{,secs}}
where:
interface-name or logical-name
The interface with which the firewall rule is associated, such as PPP 1. This can also be a logical
interface name which is simply a name that can be created (such as waffle). When a logical
interface name is specified then this name can become oos (out of service) and can be tested in
other firewall rules with the oosed keyword.
secs
The length of time, in seconds, for which the routes that are using the specified interface are
marked as out of service.
{t=secs}
Optional. The length of time in seconds the router will wait for a response the packet that
matched the rule.
{c=count}
Optional. The number of times the stateful inspection engine must trigger on the rule before the
route is marked as out of service.
{d=count}
Optional. The number of times the stateful inspection engine must trigger on the rule before the
interface is deactivated. This parameters applies to PPP interfaces only.
{r="ping"|"tcp"{,secs{,secs}}}
Optional. Specifies a recovery procedure. When a recovery procedure is specified then after the
oos timeout has expired instead of bringing the interface back into service immediately the link
is tested first. It is tested by either sending a TCP SYN packet or a ping packet to the address/port
that caused the oos condition. The secs field specifies the retry time when checking for recovery.
Only when the recovery succeeds will the interface become in service again.
Digi TransPort WR Routers User Guide
Firewall
706