How To Troubleshoot Iptables Kernel Configuration

How To Troubleshoot Iptables Kernel Configuration

If you are experiencing an iptables kernel configuration error on your computer, you should check out these troubleshooting methods.

Core Config For iptables


you can use iptables, you should better build sound support tied to the Linux kernel. Also, some functions are only useful for iptables if they are enabled. Desired kernel suboptions iptables.submenu, removes the network options menu.Functions to check:

  • Network packet filtering. The Network Packet Filtering option is located in the main settings of the network settings menu.

  • connections Tracking – This option is available when the Network Settings menu is launched from the Netfilter Configuration menu. It is necessary for many national (All of the options below are exactly the same in the Netfilter configuration menu.)

  • Support – ftp protocol FTP is a complex protocol for NAT. On Linux, NAT support for FTP requires this special kernel module.

  • Whether this table supports IP addresses is another parameter that may only be required for NAT. When buyers make a choice, a large number of additional options become available, the types of relevant tests thatYou want to run. For maximum flexibility, select everything including these advanced options. Connection state mapping support is a particularly noteworthy option as it is required for stateful packet inspection.

  • Packet filtering

    : good Although obviously does not require firewalls or NAT, this option expands the range of functions available to you. I highly recommend enabling it.

  • Target Support – This optional packet filtering option adds a rule that can be useful when building firewalls.

  • Full

    NAT – This option is required for many functions in nat, including those listed in this chapter.

  • MASQUERADE target support

    “This optional Full NAT option is required for IP masquerading”, the form of NAT is detailed in the next location “Configuring NAT” with iptables. . “Note that many of the auxiliary parameters for this package imply that this is only required if you are using a dynamic external IP address, but this is incorrect; thisis really required for IP, masking that your External IP address is definitely dynamic or not.

  • iptables kernel configuration

    Packet Mangling is a multifaceted core if needed, you really want to manipulate table described earlier. I advise you to enable it.<

  • /p> LOG
  • Purpose of support. If you want to log the actions of a firewall or router program, you can do so with this option do .



    ipchains support (2.2 style) If you are – want new good old ipchains – based on software, script you need to enable all these options. you will also need tool ipchains itself.

  • Ipfwadm

    2 (style.0) Support if this old Ipfwadm, in you need the option to include the element. they will also use the ask ipfwadm tool themselves.

iptables kernel configuration


alt="graphics/tip.gif" src=" / books/3/151/1/html/2/files/tip.gif"> Ipchains and ipfwadm are close mutually exclusive and may not be compatible with Table Awareness and Tracking IP connection options. you therefore cannot support compiling iptables for the same kernel. However, you can compile all of these tool modules as you go and choose which ones you want to use by rendering the kernel module accordingly. You may well want to compile the kernel this way if you currently have an older tool and want to port it to the newer iptables when time permits. Many distributions ship with default kernels and take advantage of this.

If you

get feature support in the form of modules, someone might need to download the most recommended modules that you are using. firewall - startup script. For example, the iptables functionality is in its ip_tables module, so your startup script may need to order insmod ip_tables . List the /lib/modules/ product /net/ipv4/netfilter directories for other modules you may need Explicit loading Manually loading modules , you can get support directly in this kernel, but this will increase pthe size of your kernel file.