After installing a Steelhead appliance, the in-path interfaces can be in one of the following two states:
In a non-operational state, when the Steelhead appliance is turned off or when the in-path interface is not enabled.
The failure configuration of the in-path interface can then either be fail-to-wire or fail-to-block:
In the fail-to-block configuration, where the by-pass card does not link the WAN and LAN interfaces together. Traffic from and to the LAN switch and WAN router is blocked.
In the output of
show interfaces inpath0_0 configured
the failure mode is
Disconnect.
In the fail-to-wire configuration, where the by-pass card does link the WAN and LAN interfaces together. The LAN switch and the WAN router are then directly connected with each other and will be able to negotiate an Ethernet link.
In the output of
show interfaces inpath0_0 configured
the failure mode is
Bypass.
In an operational state, when the by-pass card has two Ethernet links are negotiated: One between the WAN interface and the WAN router and the LAN interface and the LAN switch. The by-pass card intercepts the packets from the LAN and WAN interface and let the network stack process them.
In the output of
show interfaces inpath0_0 brief
the traffic status will be
Normal.
Figure 4.2. Inpath0_0 is operational and set to fail-to-wire
SH # show interfaces inpath0_0 brief Interface inpath0_0 state Up: yes Interface type: ethernet IP address: 10.0.0.6 Netmask: 255.255.255.0 IPv6 link-local address: fe80::20e:b6ff:fe90:352e/64 MTU: 1500 HW address: 00:0E:B6:90:35:2E Traffic status: Normal HW blockable: yes SH # show interfaces inpath0_0 configured Interface inpath0_0 configuration Enabled: yes DHCP: no Dynamic DNS DHCP: no DHCPv6: no Dynamic DNS DHCPv6: no IP address: 10.0.0.6 Netmask: 255.255.255.0 IPv6 address: MTU: 1500 Failure mode: Bypass