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iptables failing

Hi,
I am unable to get iptables to run on my linux box(running 2.6.16)
I get the following error :

#iptables -t nat -L

iptables v1.2.9: can't initialize iptables table `nat': iptables who? (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.

CONFIG_NETFILTER=y
CONFIG_NETFILTER_DEBUG=y
CONFIG_BRIDGE_NETFILTER=y

#
# Core Netfilter Configuration
#
CONFIG_NETFILTER_NETLINK=y
CONFIG_NETFILTER_NETLINK_QUEUE=y
CONFIG_NETFILTER_NETLINK_LOG=y
CONFIG_NETFILTER_XTABLES=y
CONFIG_NETFILTER_XT_TARGET_CLASSIFY=y
CONFIG_NETFILTER_XT_TARGET_CONNMARK=m
CONFIG_NETFILTER_XT_TARGET_MARK=y
CONFIG_NETFILTER_XT_TARGET_NFQUEUE=y
CONFIG_NETFILTER_XT_TARGET_NOTRACK=m
CONFIG_NETFILTER_XT_MATCH_COMMENT=y
CONFIG_NETFILTER_XT_MATCH_CONNBYTES=m
CONFIG_NETFILTER_XT_MATCH_CONNMARK=m
CONFIG_NETFILTER_XT_MATCH_CONNTRACK=m
CONFIG_NETFILTER_XT_MATCH_DCCP=y
CONFIG_NETFILTER_XT_MATCH_HELPER=m
CONFIG_NETFILTER_XT_MATCH_LENGTH=y
CONFIG_NETFILTER_XT_MATCH_LIMIT=y
CONFIG_NETFILTER_XT_MATCH_MAC=y
CONFIG_NETFILTER_XT_MATCH_MARK=y
CONFIG_NETFILTER_XT_MATCH_PHYSDEV=y
CONFIG_NETFILTER_XT_MATCH_PKTTYPE=y
CONFIG_NETFILTER_XT_MATCH_REALM=y
CONFIG_NETFILTER_XT_MATCH_SCTP=y
CONFIG_NETFILTER_XT_MATCH_STATE=m
CONFIG_NETFILTER_XT_MATCH_STRING=y
CONFIG_NETFILTER_XT_MATCH_TCPMSS=y

#
# IP: Netfilter Configuration
#
CONFIG_IP_NF_CONNTRACK=y
CONFIG_IP_NF_CT_ACCT=y
CONFIG_IP_NF_FILTER=m
...
....

Please let me know how can I overcome this issue

Thanks
Pratap

Here's a list of the modules that iptables needs.

Code:

# Module to track the state of connections

modprobe ip_conntrack



# Load the iptables active FTP module, requires ip_conntrack

modprobe ip_conntrack_ftp

  

# Load iptables NAT module when required

modprobe iptable_nat

 

# Module required for active an FTP server using NAT

modprobe ip_nat_ftp

You can check and see if you have those modules loaded by running lsmod. If not run, like above, modprobe iptable_nat (which is probably the only one you need). If it says it can't find the module, then you need to recompile your kernel to include either the iptables_nat module or have it built in.

Hi,
Thanks for the information. Recompile means I have to set the
CONFIG_IP_NF_FILTER=y instead of CONFIG_IP_NF_FILTER=m is it ?

After I do this I need to rebuild my kernel .Should i also to make some re-build the iptables utility ?

Thanks
Pratap

First try loading up the module. If your current config has

Code:

CONFIG_IP_NF_FILTER=m

then it was compiled as a module.

Just run

Code:

modprobe iptable_nat

Hi ,
Thanks for the help.
I have another query.
Is it necessary to build netfilter as a module always ? If we build it into the kernel , still iptables should work right ?
Please let me know

Thanks
Pratap