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ASA 5505 Dual ISP setup


I need help setting up my ASA5505 Sec+ license to work with 2 ISPs. Right now it works just fine with one WAN interface, and I set second one as backup but not getting any traffic through WAN2 (backup 0/2). Both ISPs provide dynamic IP address and I set ASA to obtain IP address for "outside" and "backup" via DHCP. I need ASA set to switch over second ISP link ("backup" when first one is done or there is some problem and the traffic is not going through it. When primary ISP ("outside") is back, ASA should switch to primary ISP back.

Result of the command: "sho run"
: Saved
ASA Version 8.0(4) 
hostname asa
enable password OmnnXRU1dg.mR encrypted
passwd 2KFQn.2KYOU encrypted
interface Vlan1
 nameif inside
 security-level 100
 ip address 
 ospf cost 10
interface Vlan2
 nameif outside
 security-level 0
 ip address dhcp setroute 
 ospf cost 10
interface Vlan3
 nameif backup
 security-level 0
 ip address dhcp setroute 
 ospf cost 10
interface Ethernet0/0
 switchport access vlan 2
interface Ethernet0/1
 switchport access vlan 3
interface Ethernet0/2
interface Ethernet0/3
interface Ethernet0/4
interface Ethernet0/5
interface Ethernet0/6
interface Ethernet0/7
banner login  **************************************************************************************
ftp mode passive
clock timezone EST -4
clock summer-time EDT recurring
access-list icmp_permit extended permit icmp any any 
access-list SSL extended permit tcp any any eq ssh 
pager lines 24
logging enable
logging asdm informational
mtu inside 1500
mtu outside 1500
mtu backup 1500
no failover
icmp unreachable rate-limit 1 burst-size 1
asdm image disk0:/asdm-615.bin
no asdm history enable
arp timeout 14400
global (outside) 1 interface
nat (inside) 1
access-group icmp_permit in interface outside
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
dynamic-access-policy-record DfltAccessPolicy
http server enable
http inside
no snmp-server location
no snmp-server contact
snmp-server enable traps snmp authentication linkup linkdown coldstart
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
telnet timeout 5
ssh inside
ssh timeout 5
console timeout 30
dhcpd auto_config outside
dhcpd address inside
dhcpd auto_config outside interface inside
dhcpd enable inside
threat-detection basic-threat
threat-detection statistics port
threat-detection statistics protocol
threat-detection statistics access-list
threat-detection statistics tcp-intercept rate-interval 30 burst-rate 400 average-rate 200
ntp server source outside
ntp server source outside prefer
class-map inspection_default
 match default-inspection-traffic
policy-map type inspect dns preset_dns_map
  message-length maximum 512
policy-map global_policy
 class inspection_default
  inspect dns preset_dns_map 
  inspect ftp 
  inspect h323 h225 
  inspect h323 ras 
  inspect rsh 
  inspect rtsp 
  inspect esmtp 
  inspect sqlnet 
  inspect skinny  
  inspect sunrpc 
  inspect xdmcp 
  inspect sip  
  inspect netbios 
  inspect tftp 
  inspect pptp 
  inspect icmp 
policy-map global-policy
service-policy global_policy global
prompt hostname context 
: end

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1 Solution
Here's a link that should help you out.


"In order to achieve this redundancy, the security appliance associates a static route with a monitoring target
that you define. The service level agreement (SLA) operation monitors the target with periodic Internet
Control Message Protocol (ICMP) echo requests. If an echo reply is not received, the object is considered
down, and the associated route is removed from the routing table. A previously configured backup route is
used in place of the route that is removed. While the backup route is in use, the SLA monitor operation
continues to try to reach the monitoring target. Once the target is available again, the first route is replaced in
the routing table, and the backup route is removed."

MACROLEVELAuthor Commented:
I already found this example


but I do not have enough experience to follow it. I need detailed instructions either using CLI or ASDM how to set it up for dynamic IPs. My first provider is cable with modem in bridged mode, second (backup) line is DSL with some kind of router built-in and DHCP server . I do see both IP addresses inside ASDM so ASA did assign them to appropriate interfaces.
I haven't tested this but I believe this is all you're missing.  

global (backup) 1 interface

route outside <Default Gateway of outside from DHCP> 1 track 1

route backup <Default Gateway of backup from DHCP> 254

(This route has an administrative distance of 254 so it will not be used if the route with an AD of 1 is available.)

sla monitor 123
 type echo protocol ipIcmpEcho <external IP you want to monitor to verify that outside is up> interface outside
 num-packets 3
 frequency 10

sla monitor schedule 123 life forever start-time now
track 1 rtr 123 reachability
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MACROLEVELAuthor Commented:
Is the GW address for dynamic WAN IPs always permanent? I mean, periodically I'm getting new IP address from ISP. Will the GW address change as well so I have to change it on ASA as well? Also, is there a way to see what is the GW address from ASA for each outside interface?
One of the problems with DHCP on the WAN is that your providers will most likely change you're IP from time to time; if they keep you in the same subnet youll be fine.  You may want to look into the cost of getting a static IPs.

You should be able use the command show route outside to determine your gateway
So could we also enable the following:

crypto map vpn interface outside
crypto map vpn interface backup
crypto isakmp enable outside
crypto isakmp enable backup

Would it move the tunneling over to the backup ISP?
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