Redhat 7.2 - Deleting ipchains Notes: http://www.tldp.org/HOWTO/IPCHAINS-HOWTO-4.html First list the chains by chain number: # ipchains -L --line Chain input (policy ACCEPT): num target prot opt source destination ports 1 ACCEPT udp ------ orlhbcns1.harcourtbrace.com anywhere domain -> 1025:65535 2 ACCEPT udp ------ harcourt.harcourtbrace.com anywhere domain -> 1025:65535 3 ACCEPT tcp -y---- anywhere anywhere any -> smtp 4 ACCEPT tcp -y---- anywhere anywhere any -> http 5 ACCEPT tcp -y---- anywhere anywhere any -> ftp 6 ACCEPT tcp -y---- anywhere anywhere any -> ssh 7 ACCEPT udp ------ anywhere anywhere bootps:bootpc -> bootps:bootpc 8 ACCEPT udp ------ anywhere anywhere bootps:bootpc -> bootps:bootpc 9 ACCEPT all ------ anywhere anywhere n/a 10 REJECT tcp -y---- anywhere anywhere any -> 0:1023 11 REJECT tcp -y---- anywhere anywhere any -> nfs 12 REJECT udp ------ anywhere anywhere any -> 0:1023 13 REJECT udp ------ anywhere anywhere any -> nfs 14 REJECT tcp -y---- anywhere anywhere any -> x11:6009 15 REJECT tcp -y---- anywhere anywhere any -> xfs Chain forward (policy ACCEPT): Chain output (policy ACCEPT): Decide the chain you wish to remove and remove it: (in this case I want to remove line item # 11 (nfs - because I want to temporarily export a cdrom) of the chain "input") # ipchains -D input 11 # ipchains -L --line Chain input (policy ACCEPT): num target prot opt source destination ports 1 ACCEPT udp ------ orlhbcns1.harcourtbrace.com anywhere domain -> 1025:65535 2 ACCEPT udp ------ harcourt.harcourtbrace.com anywhere domain -> 1025:65535 3 ACCEPT tcp -y---- anywhere anywhere any -> smtp 4 ACCEPT tcp -y---- anywhere anywhere any -> http 5 ACCEPT tcp -y---- anywhere anywhere any -> ftp 6 ACCEPT tcp -y---- anywhere anywhere any -> ssh 7 ACCEPT udp ------ anywhere anywhere bootps:bootpc -> bootps:bootpc 8 ACCEPT udp ------ anywhere anywhere bootps:bootpc -> bootps:bootpc 9 ACCEPT all ------ anywhere anywhere n/a 10 REJECT tcp -y---- anywhere anywhere any -> 0:1023 11 REJECT udp ------ anywhere anywhere any -> 0:1023 12 REJECT udp ------ anywhere anywhere any -> nfs 13 REJECT tcp -y---- anywhere anywhere any -> x11:6009 14 REJECT tcp -y---- anywhere anywhere any -> xfs Chain forward (policy ACCEPT): Chain output (policy ACCEPT): Or I could just remove the enitre chain for input: # ipchains -X input if you see this error: ipchains: Device or resource busy it means the chain is activly filtering something. Likely you teleneted in to run this command instead of doing it from the console didn't you. Tsk-tsk. ;-) You can flush all the chains with the command: # ipchains -F forward