After a few years in use. We have seen Cisco 871 and 851 routers that would hang if you had a single download that was more than 100M large. It is intermittent. Sometimes the problem goes away, sometimes it happens on very small downloads (just a 10KB web page). It seems that the just about all the downloads eventually finish, but the bigger the download the longer the hang.
Is there a way to resolve this? (short of router replacement which is what we have been doing)
We are revisiting this on a Cisco 851 that is one year and two months old. At this point, similar hangs seem to be occurring, at a much less important scale. In this case, the customer has purchased a 30Mbps up/down internet connection, and they are only able to get 5Mbps/20Mbps up/down. At times, download speed is reduced to 5Mbps.
I will attempt what has already been suggested below next time I am out there (hopefully next week) and edit in my findings.
I an ACL on Vlan1 and on the Fa4. I also have a few ACLs that were replaced and are not used. The ACLs are about 45 lines and about half the lines are remarks. I have posted the config below. Personal information is masked with words such as
WAN IP or
If you have suggestions such as performance improvements for the configuration code, or information such as whether I can expect 30Mbps on an 851, that would be appreciated.
Current configuration : 18157 bytes ! version 12.4 no service pad service tcp-keepalives-in service tcp-keepalives-out service timestamps debug datetime msec localtime show-timezone service timestamps log datetime msec localtime show-timezone service password-encryption service sequence-numbers ! hostname HIDDEN ! boot-start-marker boot-end-marker ! logging buffered 51200 logging console critical enable secret 5 --GIBBERISH--- ! aaa new-model ! ! aaa authentication login local_authen local aaa authorization exec local_author local ! ! aaa session-id common clock timezone EST -5 ! crypto pki trustpoint TP-self-signed-4140887523 enrollment selfsigned subject-name cn=IOS-Self-Signed-Certificate-4140887523 revocation-check none rsakeypair TP-self-signed-4140887523 ! ! dot11 syslog no ip source-route no ip dhcp use vrf connected ip dhcp binding cleanup interval 60 ip dhcp excluded-address 10.10.10.1 ip dhcp excluded-address 192.168.1.1 ! ip dhcp pool ccp-pool import all network 10.10.10.0 255.255.255.248 default-router 10.10.10.1 lease 0 2 ! ip dhcp pool sdm-pool1 import all network 192.168.1.0 255.255.255.0 dns-server --DNS Server 1-- --DNS Server 2-- default-router 192.168.1.1 ! ! ip cef ip inspect name DEFAULT100 appfw DEFAULT100 ip inspect name DEFAULT100 cuseeme ip inspect name DEFAULT100 ftp ip inspect name DEFAULT100 h323 ip inspect name DEFAULT100 icmp ip inspect name DEFAULT100 rcmd ip inspect name DEFAULT100 realaudio ip inspect name DEFAULT100 rtsp ip inspect name DEFAULT100 esmtp ip inspect name DEFAULT100 sqlnet ip inspect name DEFAULT100 streamworks ip inspect name DEFAULT100 tftp ip inspect name DEFAULT100 tcp ip inspect name DEFAULT100 udp ip inspect name DEFAULT100 vdolive ip inspect name DEFAULT100 https ip inspect name DEFAULT100 dns no ip bootp server no ip domain lookup ip domain name noexist.example.com ip name-server --DNS Server 2-- ip name-server --DNS Server 1-- ! appfw policy-name DEFAULT100 application im aol service default action reset service text-chat action reset server deny name login.oscar.aol.com server deny name toc.oscar.aol.com server deny name oam-d09a.blue.aol.com application im msn service default action reset service text-chat action reset server deny name messenger.hotmail.com server deny name gateway.messenger.hotmail.com server deny name webmessenger.msn.com application http port-misuse im action reset alarm application im yahoo service default action reset service text-chat action reset server deny name scs.msg.yahoo.com server deny name scsa.msg.yahoo.com server deny name scsb.msg.yahoo.com server deny name scsc.msg.yahoo.com server deny name scsd.msg.yahoo.com server deny name messenger.yahoo.com server deny name cs16.msg.dcn.yahoo.com server deny name cs19.msg.dcn.yahoo.com server deny name cs42.msg.dcn.yahoo.com server deny name cs53.msg.dcn.yahoo.com server deny name cs54.msg.dcn.yahoo.com server deny name ads1.vip.scd.yahoo.com server deny name radio1.launch.vip.dal.yahoo.com server deny name in1.msg.vip.re2.yahoo.com server deny name data1.my.vip.sc5.yahoo.com server deny name address1.pim.vip.mud.yahoo.com server deny name edit.messenger.yahoo.com server deny name http.pager.yahoo.com server deny name privacy.yahoo.com server deny name csa.yahoo.com server deny name csb.yahoo.com server deny name csc.yahoo.com ! ! ! username surfn privilege 15 secret 5 $1$1hrm$0yfIN0jK56rOm9cXfm2a21 ! ! archive log config hidekeys ! ! ip tcp synwait-time 10 ip ssh time-out 60 ip ssh authentication-retries 2 ! ! ! interface Null0 no ip unreachables ! interface FastEthernet0 ! interface FastEthernet1 ! interface FastEthernet2 ! interface FastEthernet3 ! interface FastEthernet4 description $ES_WAN$$FW_OUTSIDE$ ip address --WAN IP-- 255.255.255.0 ip access-group 123 in ip verify unicast reverse-path no ip redirects no ip unreachables no ip proxy-arp ip inspect DEFAULT100 out ip nat outside ip virtual-reassembly ip route-cache flow duplex auto speed auto ! interface Vlan1 description $ETH-SW-LAUNCH$$INTF-INFO-HWIC 4ESW$$ES_LAN$$FW_INSIDE$ ip address 192.168.1.1 255.255.255.0 ip access-group 102 in no ip redirects no ip unreachables no ip proxy-arp ip nat inside ip virtual-reassembly ip route-cache flow ip tcp adjust-mss 1452 ! ip forward-protocol nd ip route 0.0.0.0 0.0.0.0 --ISP Gateway-- ! ip http server ip http access-class 2 ip http authentication local ip http secure-server ip http timeout-policy idle 60 life 86400 requests 10000 ip nat inside source list 1 interface FastEthernet4 overload ! logging trap debugging access-list 1 remark Telnet, SSH access access-list 1 permit 192.168.1.0 0.0.0.255 access-list 1 deny any access-list 2 remark HTTP, HTTPS access access-list 2 permit 192.168.1.0 0.0.0.255 access-list 2 deny any access-list 101 HIDDEN access-list 102 HIDDEN access-list 121 HIDDEN access-list 122 HIDDEN access-list 123 HIDDEN no cdp run ! control-plane ! banner exec ^C % Password expiration warning. ----------------------------------------------------------------------- Cisco Configuration Professional (Cisco CP) is installed on this device and it provides the default username "cisco" for one-time use. If you have already used the username "cisco" to login to the router and your IOS image supports the "one-time" user option, then this username has already expired. You will not be able to login to the router with this username after you exit this session. It is strongly suggested that you create a new username with a privilege level of 15 using the following command. username <myuser> privilege 15 secret 0 <mypassword> Replace <myuser> and <mypassword> with the username and password you want to use. ----------------------------------------------------------------------- ^C banner login ^CCAuthorized access only! Disconnect IMMEDIATELY if you are not an authorized user!^C ! line con 0 login authentication local_authen no modem enable transport output telnet line aux 0 login authentication local_authen transport output telnet line vty 0 4 access-class 100 in privilege level 15 authorization exec local_author login authentication local_authen transport input telnet ssh ! scheduler max-task-time 5000 scheduler allocate 4000 1000 scheduler interval 500 end