Cisco 7604 Configuration Guide - Page 117

Unsupported Features in Transparent Mode, Unsupported Feature, Description

Page 117 highlights

Chapter 5 Configuring the Firewall Mode Transparent Mode Overview • For multiple context mode, each context must use different interfaces; you cannot share an interface across contexts. The only exception to this is for an optional management VLAN, which can be shared across multiple contexts. • For multiple context mode, each context typically uses different subnets. You can use overlapping subnets, but your network topology requires router and NAT configuration to make it possible from a routing standpoint. • You must use an extended access list to allow Layer 3 traffic, such as IP traffic, through the FWSM. You can also optionally use an EtherType access list to allow non-IP traffic through. Unsupported Features in Transparent Mode Table 5-1 lists features that are not supported in transparent mode. Table 5-1 Unsupported Features in Transparent Mode Unsupported Feature Description DHCP relay The transparent firewall can act as a DHCP server, but it does not support the DHCP relay commands. DHCP relay is not required because you can allow DHCP traffic to pass through using an extended access list. Dynamic routing protocols You can, however, add static routes for traffic originating on the FWSM. You can also allow dynamic routing protocols through the FWSM using an extended access list. IPv6 for the bridge group IP address or You can, however, pass the IPv6 EtherType using an management interface IP address EtherType access list. LoopGuard on the switch Do not enable LoopGuard globally on the switch if the FWSM is in transparent mode. LoopGuard is automatically applied to the internal EtherChannel between the switch and the FWSM, so after a failover and a failback, LoopGuard causes the secondary unit to be disconnected because the EtherChannel goes into the err-disable state. Multicast You can, however, allow multicast traffic through the FWSM by allowing it in an extended access list. Remote access VPN for management You can use site-to-site VPN for management. OL-20748-01 Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM 5-11

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5-11
Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
OL-20748-01
Chapter 5
Configuring the Firewall Mode
Transparent Mode Overview
For multiple context mode, each context must use different interfaces; you cannot share an interface
across contexts. The only exception to this is for an optional management VLAN, which can be
shared across multiple contexts.
For multiple context mode, each context typically uses different subnets. You can use overlapping
subnets, but your network topology requires router and NAT configuration to make it possible from
a routing standpoint.
You must use an extended access list to allow Layer 3 traffic, such as IP traffic, through the FWSM.
You can also optionally use an EtherType access list to allow non-IP traffic through.
Unsupported Features in Transparent Mode
Table 5-1
lists features that are not supported in transparent mode.
Table 5-1
Unsupported Features in Transparent Mode
Unsupported Feature
Description
DHCP relay
The transparent firewall can act as a DHCP server, but it does
not support the DHCP relay commands. DHCP relay is not
required because you can allow DHCP traffic to pass through
using an extended access list.
Dynamic routing protocols
You can, however, add static routes for traffic originating on
the FWSM. You can also allow dynamic routing protocols
through the FWSM using an extended access list.
IPv6 for the bridge group IP address or
management interface IP address
You can, however, pass the IPv6 EtherType using an
EtherType access list.
LoopGuard on the switch
Do not enable LoopGuard globally on the switch if the
FWSM is in transparent mode. LoopGuard is automatically
applied to the internal EtherChannel between the switch and
the FWSM, so after a failover and a failback, LoopGuard
causes the secondary unit to be disconnected because the
EtherChannel goes into the err-disable state.
Multicast
You can, however, allow multicast traffic through the FWSM
by allowing it in an extended access list.
Remote access VPN for management
You can use site-to-site VPN for management.