Router connected to cable modem by Ethernet port cannot get IP address from DHCP.

I have an ethernet cable on Fa0/0 connecting my 1841 router to my cable modem. The issue is that the router cannot obtain an IP address via DHCP when I have the "ACL-OUTSIDE-IN" ACL applied inbound on the Fa0/0 interface. I tried to allow all BOOTP and BOOTPS traffic in my ACL, but still no luck. I really don't want to run the router without a simple ACL firewall and connect it to the internet. When I take off the ACL off of Fa0/0, the router is able to get an IP address via DHCP.
Router#sh run
Building configuration...
Current configuration : 10736 bytes
! Last configuration change at 18:14:42 MST Fri Nov 16 2012 by matt.chan
version 12.4
service nagle
service timestamps debug datetime msec localtime show-timezone year
service timestamps log datetime msec localtime show-timezone year
service password-encryption
hostname Router
boot-start-marker
boot system flash:c1841-advipservicesk9-mz.124-25f.bin
boot-end-marker
logging count
logging userinfo
logging buffered 1048576 informational
enable secret 5 <removed>
aaa new-model
aaa authentication login AUTH-LOCAL local-case
aaa session-id unique
memory-size iomem 25
clock timezone MST -7
ip cef
ip nbar pdlm flash:directconnect.pdlm
ip nbar pdlm flash:citrix.pdlm
ip nbar pdlm flash:bittorrent.pdlm
ip nbar custom steam destination udp range 27000 27030
ip nbar custom rdp destination tcp range 3389 3391 55402
ip domain lookup source-interface FastEthernet0/0
ip name-server 8.8.8.8
ip inspect name fa0/0_inspect_ou icmp router-traffic timeout 10
ip inspect name fa0/0_inspect_ou ftp timeout 300
ip inspect name fa0/0_inspect_ou udp router-traffic timeout 120
ip inspect name fa0/0_inspect_ou tcp router-traffic timeout 300
login block-for 60 attempts 4 within 60
login quiet-mode access-class ACL-ACCESS-QUIET
password encryption aes
crypto pki trustpoint TP-self-signed-1755372391
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-1755372391
revocation-check none
rsakeypair TP-self-signed-1755372391
crypto pki certificate chain TP-self-signed-1755372391
certificate self-signed 01
3082023F 308201A8 A0030201 02020101 300D0609 2A864886 F70D0101 04050030
31312F30 2D060355 04031326 494F532D 53656C66 2D536967 6E65642D 43657274
69666963 6174652D 31373535 33373233 3931301E 170D3132 31313137 30313130
35325A17 0D323030 31303130 30303030 305A3031 312F302D 06035504 03132649
4F532D53 656C662D 5369676E 65642D43 65727469 66696361 74652D31 37353533
37323339 3130819F 300D0609 2A864886 F70D0101 01050003 818D0030 81890281
8100D53F 9EB5B123 3103A4D5 82E786F7 F91C2DE5 9E409A22 80AF78F6 812F624A
89FE9103 73C4AAAB 13FF880D F628607D 6888AC49 18BEDD77 778F0DB1 F9A796E9
E92717CD 6DD19450 5066620A 91278C33 E38349EA 92B8C671 80761609 0AC46E6F
2C8C6BCF ABC7E1F7 A64BD28C C85477FE B23F8A7C 555ECDF9 CE461B8D 6C017370
0ED70203 010001A3 67306530 0F060355 1D130101 FF040530 030101FF 30120603
551D1104 0B300982 074E5543 4C455553 301F0603 551D2304 18301680 146CA2E0
936C651F E2ED4DCD D7025FF3 2AB029E0 95301D06 03551D0E 04160414 6CA2E093
6C651FE2 ED4DCDD7 025FF32A B029E095 300D0609 2A864886 F70D0101 04050003
8181004A AFA4D07C 1424DE0E EF3F17F2 BB1EA63B CB17C13D 1AEA31A1 BAB6AF77
DB6EA8A2 2117DCD1 5530A18C 3618D568 CC7EF520 E039ACBD DA906352 BB7E51BD
0954490C B2AB30C2 FBBE4738 C214BE1C CB63FFEA BAFC46E0 3DC419EE 714B9ABD
144A21E3 3E54C103 FF47FAF1 412FE5C4 59ACD1FE FD72356B C8DC04C3 E2EDF275 45954C
quit
username <removed secret 5 <removed>
ip ssh maxstartups 10
ip ssh time-out 60
ip ssh authentication-retries 2
ip ssh port 2226 rotary 1
ip ssh version 2
class-map match-all Zuri-YouTube-Class
match access-group name NAT-Pool-Zuri-WLAN
match protocol http host "*youtube.com*"
policy-map PMAP-QOS-VTI-IN
description QOS FOR TU0
class class-default
shape peak 1512000
policy-map PMAP-QOS-VTI-OUT
description QOS FOR TU0
class class-default
shape peak 512000
crypto isakmp policy 1
encr aes 256
authentication pre-share
group 5
lifetime 43200
crypto isakmp key 6 <removed> address <removed>
crypto isakmp invalid-spi-recovery
crypto isakmp keepalive 10 5 periodic
crypto ipsec transform-set EDGE-TS ah-sha-hmac esp-aes 256
crypto ipsec profile EDGE
set security-association lifetime kilobytes 256000
set transform-set EDGE-TS
set pfs group5
interface Loopback0
no ip address
interface Tunnel0
description "VTI Link"
bandwidth 4000
ip address 172.20.0.2 255.255.255.0
ip mtu 1400
ip nbar protocol-discovery
ip nat inside
ip virtual-reassembly
ip tcp adjust-mss 1360
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 7 12090011003E5A0C0F186E752220211B4A
keepalive 10 5
tunnel source FastEthernet0/0
tunnel destination <removed>
tunnel mode ipsec ipv4
tunnel path-mtu-discovery
tunnel protection ipsec profile EDGE
service-policy output PMAP-QOS-VTI-OUT
hold-queue 75 out
interface FastEthernet0/0
description "Link to ISP"
bandwidth 4000
ip address dhcp
ip access-group ACL-OUTSIDE-IN in
no ip proxy-arp
ip nbar protocol-discovery
ip nat outside
ip inspect fa0/0_inspect_ou out
ip virtual-reassembly
ip ospf cost 1
duplex auto
speed auto
no keepalive
no cdp enable
interface FastEthernet0/1
description "Link to LAN"
ip address 172.16.0.1 255.255.255.248
ip access-group ACL-INSIDE-IN in
no ip proxy-arp
ip nbar protocol-discovery
ip nat inside
ip virtual-reassembly
ip ospf cost 1
ip ospf priority 255
duplex auto
speed auto
no keepalive
router ospf 1
log-adjacency-changes
redistribute static subnets
passive-interface default
no passive-interface Tunnel0
network 172.20.0.0 0.0.0.3 area 0
ip forward-protocol nd
ip route 10.0.0.0 255.0.0.0 Null0 name "Class A Private"
ip route 172.16.0.0 255.240.0.0 Null0 name "Class B Private"
ip route 172.17.0.0 255.255.0.0 FastEthernet0/1 172.16.0.2 name "Home WLAN"
ip route 172.19.73.31 255.255.255.255 Null0
ip route 172.27.0.0 255.255.0.0 Tunnel0 172.20.0.1 name "IPsec GRE Tunnel"
ip route 192.168.0.0 255.255.0.0 Null0 name "Class C Private"
ip route 192.168.0.0 255.255.255.0 Tunnel0 172.20.0.1 name "VLAN 70"
ip route 192.168.100.1 255.255.255.255 FastEthernet0/0 70.162.0.1 permanent name "CABLE MODEM MANAGEMENT"
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0 dhcp 253
ip dns server
no ip http server
ip http authentication local
ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
ip nat translation tcp-timeout 300
ip nat translation udp-timeout 120
ip nat translation max-entries 2048
ip nat inside source list ACL-NAT-172.16.0.0/29 interface FastEthernet0/0 overload
ip nat inside source list ACL-NAT-MANAGEMENT interface FastEthernet0/0 overload
ip nat inside source static tcp 172.16.0.4 22 interface FastEthernet0/0 2227
ip nat inside source static tcp 172.16.0.5 3389 interface FastEthernet0/0 3391
ip nat inside source static tcp 172.16.0.3 3389 interface FastEthernet0/0 3390
ip nat inside source static tcp 172.16.0.4 80 interface FastEthernet0/0 8084
ip access-list standard ACL-ACCESS-QUIET
permit 216.161.180.16
permit 172.16.0.0 0.1.255.255
permit 172.27.0.0 0.0.127.255
permit 172.20.0.0 0.0.0.3
ip access-list standard ACL-NAT-172.16.0.0/29
permit 172.16.0.0 0.0.0.7
ip access-list standard ACL-NAT-172.17.0.0/24
permit 172.17.0.0 0.0.0.255
ip access-list standard ACL-NAT-172.17.1.0/24
permit 172.17.1.0 0.0.0.255
ip access-list standard ACL-SNMP
permit 172.16.0.4
ip access-list extended ACL-CRY-MAP
ip access-list extended ACL-INSIDE-IN
deny   ip host 172.16.0.2 172.27.0.0 0.0.127.255
deny   ip host 172.16.0.2 172.20.0.0 0.0.0.3
permit ip 172.17.0.0 0.0.0.255 any
permit ip 172.16.0.0 0.0.0.7 any
permit ip 172.17.1.0 0.0.0.255 any
ip access-list extended ACL-NAT-MANAGEMENT
permit tcp host 172.27.10.11 eq 3389 host 72.166.77.196
ip access-list extended ACL-OUTSIDE-IN
deny   ip 10.0.0.0 0.255.255.255 any
deny   ip 172.16.0.0 0.15.255.255 any
deny   ip 192.168.0.0 0.0.255.255 any
permit tcp any any range 3390 3391
permit udp any any eq bootpc
permit udp any any eq bootps
permit tcp any any range 2226 2228
permit tcp any any range 8081 8084
permit icmp any any echo
permit icmp any any net-unreachable
permit icmp any any host-unreachable
permit icmp any any port-unreachable
permit icmp any any parameter-problem
permit icmp any any packet-too-big
permit icmp any any administratively-prohibited
permit icmp any any source-quench
permit icmp any any ttl-exceeded
deny   icmp any any
deny   ip any any
ip access-list log-update threshold 10
logging history informational
logging trap debugging
logging 172.17.228.17
logging 172.17.228.10
control-plane
line con 0
exec-timeout 15 0
privilege level 15
logging synchronous
login authentication AUTH-LOCAL
line aux 0
login authentication AUTH-LOCAL
line vty 0 4
exec-timeout 60 0
privilege level 15
logging synchronous
login authentication AUTH-LOCAL
rotary 1
transport input ssh
scheduler allocate 20000 1000
ntp clock-period 17178311
ntp source FastEthernet0/0
ntp server 148.167.132.201
end

Hi Matt,
Try adding below line
ip access-list extended ACL-OUTSIDE-IN
permit udp any eq bootpc any eq bootps
Regards
Najaf
Please rate when applicable or helpful !!!

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router_2501(config)#int e0
router_2501(config-if)#shut
01:52:32: %LINK-5-CHANGED: Interface Ethernet0, changed state to administrativel
y down
router_2501(config-if)#no shut
01:52:35: DHCP: SRelease attempt # 1 for entry:
01:52:35: Temp IP addr: 10.49.205.119 for peer on Interface: Ethernet0
01:52:35: Temp sub net mask: 255.255.240.0
01:52:35: DHCP Lease server: 172.19.73.16, state: 7 Releasing
01:52:35: DHCP transaction id: 1B02
01:52:35: Lease: 86400 secs, Renewal: 43200 secs, Rebind: 75600 secs
01:52:35: Next timer fires after: 00:00:00
01:52:35: Retry count: 1 Client-ID: cisco-0000.0c3f.249d-Et0
01:52:35: DHCP: SRelease placed Server ID option: 172.19.73.16
01:52:35: DHCP: SRelease: 277 bytes
01:52:36: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up
01:52:36: DHCP: SRelease attempt # 2 for entry:
01:52:36: Temp IP addr: 10.49.205.119 for peer on Interface: Ethernet0
01:52:36: Temp sub net mask: 255.255.240.0
01:52:36: DHCP Lease server: 172.19.73.16, state: 7 Releasing
01:52:36: DHCP transaction id: 1B02
01:52:36: Lease: 86400 secs, Renewal: 43200 secs, Rebind: 75600 secs
01:52:36: Next timer fires after: 00:00:00
01:52:36: Retry count: 2 Client-ID: cisco-0000.0c3f.249d-Et0
01:52:36: DHCP: SRelease placed Server ID option: 172.19.73.16
01:52:36: DHCP: SRelease: 277 bytes
01:52:37: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed sta
te to up
01:52:37: DHCP: SRelease attempt # 3 for entry:
01:52:37: Temp IP addr: 10.49.205.119 for peer on Interface: Ethernet0
01:52:37: Temp sub net mask: 255.255.240.0
01:52:37: DHCP Lease server: 172.19.73.16, state: 7 Releasing
01:52:37: DHCP transaction id: 1B02
01:52:37: Lease: 86400 secs, Renewal: 43200 secs, Rebind: 75600 secs
01:52:37: Next timer fires after: 00:00:00
01:52:37: Retry count: 3 Client-ID: cisco-0000.0c3f.249d-Et0
01:52:37: DHCP: SRelease placed Server ID option: 172.19.73.16
01:52:37: DHCP: SRelease: 277 bytes
01:53:08: DHCP: QScan: Purging entry
01:53:08: DHCP: deleting entry 240414 10.49.205.119 from list
01:53:08: Temp IP addr: 10.49.205.119 for peer on Interface: Ethernet0
01:53:08: Temp sub net mask: 255.255.240.0
01:53:08: DHCP Lease server: 172.19.73.16, state: 8 Purging
01:53:08: DHCP transaction id: 1B02
01:53:08: Lease: 86400 secs, Renewal: 43200 secs, Rebind: 75600 secs
01:53:08: No timer running
01:53:08: Retry count: 0 Client-ID: cisco-0000.0c3f.249d-Et0
router_2501(config-if)#

Airport express won't connect to cable modem

We recently moved to a new residence and just had internet service installed by a technician. Unfortunately, I didn't have my Airport Express handy while he was here, so he simply connected my Macbook Pro directly to the cable modem via ethernet cable. When I found my Airport Express, I disconnected the Macbook Pro from the cable modem and connected the Airport Express to the modem via the same ethernet cable and powered up. The Airport Express began flashing yellow but the flashing yellow never did turn the steady green that indicates the Airport Express is receiving the signal. I called my internet provider but they don't deal with router issues. What can I do?

Cable modems "remember" the device that is connected. Your modem is "remembering" your computer and looking for it when you connect the AirPort Express, so it will not connect to the AirPort Express.
You need to push the reset button on the modem and then power off the modem
Power off everything else on the network...all computers and devices
Wait 15 minutes
Make sure that the ethernet cable from the modem is connected to the AirPort Express
Power up the modem only and let it run 3-4 minutes by itself
Power up the AirPort Express and let it run a few moments
Power up each computer and device one at a time
Check for proper operation.
If...you are switching from a previous DSL service to cable, you may need to reconfigure the AirPort Express. Post back for more info on this.
Message was edited by: Bob Timmons

Use base station as router instead of cable modem

I have a cable modem that is also a router connected by a wire to the Airport extreme base station. Officially, the Airport should be used as a bridge, disabling the distribute IP option. The thing is this modem ***** and I can't replace it because its from my cable company and also used as IP phone. I would like the Airport to be the DHCP router and handle all the NAT. However, when I turn on the distribute IP option the Airport is freezing.
Note that there is no way to shut down DHCP router on the cable modem.
The modem uses 192.168.1.1 type addresses. Should the airport distribution also be configured to this type of address or to a different one, such as 10.0.0.1.
Is there an optimal way to use the airport DHCP and NAT, bypassing the DHCP of the modem?
Thanks,
Y.

The disabling of the DHCP in the router is a must. Without first disabling the router, you will have DHCP conflicts.

Router connected to cable modem by Ethernet port cannot get IP address from DHCP.

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