1
vote
0answers
56 views

iptables xt_recent change in kernel without modules

is it possible to change xt_recent module parameters when it is compiled into kernel ? most of the info on internet suggest setting it by modprobe but that is not the case in my setup as I have ...
0
votes
0answers
80 views

Why does firehol generate an iptables ACCEPT rule on top?

Firehol generates iptables rules from a convenient configuration file. In my /etc/firehol/firehol.conf I have the following very simple configuration to allow incoming connections on http, https and ...
3
votes
1answer
193 views

What does nf_conntrack.acct really do?

I've found the kernel parameter nf_conntrack.acct interesting, in that the kernel documentation merely says "Enable connection tracking flow accounting". I've appended this to grub and rebooted and I ...
7
votes
1answer
2k views

Unexpectedly shrunk window

I run a major media upload/download site and I noticed these: Is this serious or background noise due to the big file sizes and is there any tweaks I can add to /etc/sysctl.conf to improve and ...
1
vote
3answers
348 views

High CPU usage in random IP/Port UDP DDoS

I have been getting these UDP floods with random IPs and ports. randomip:randomport -> myip:randomport 0 byte payload For some reason it is using a lot of CPU. Here is the results of perf top -e ...
2
votes
0answers
201 views

Monitoring Linux Kernel Space Processing

I'm running two "services" that are served in linux kernel-space: Linux Netfilter Firewall ("iptables") Linux Virtual Server Loadbalancer ("IPVS", "LVS") Now I want to (performance-)monitor my ...
0
votes
1answer
942 views

iptables DNAT from loopback

I'm trying to understand the limitations of using iptables DNAT with loopback addresses. Consider we have an application which can connect only to 127.0.0.1; the obvious solution to make server and ...
1
vote
2answers
312 views

Changing VPS provider, kernels changed…broke my iptables how do I fix it?

Hi guys I am changing host providers and I was running centOS 5.7 on my machine with the kernel 2.6.18-274.el5 On my new vps the kernel is 2.6.32.12 and the OS is centOS 5.6...they did not have 5.7 ...
0
votes
1answer
2k views

iptables v1.4.10: can't initialize iptables table `NAT': Table does not exist

xxx:~# iptables -t NAT -A PREROUTING -d xxx.xxx.xxx.xxx -j DNAT --to-destination 10.0.1.2 WARNING: All config files need .conf: /etc/modprobe.d/bad_list, it will be ignored in a future release. ...
1
vote
1answer
457 views

Documentation on Kernel variables

I was wondering if some one can point to some good documentation which can give me detailed information about some kernel variable. I am right now mostly interested in the following variables / ...
1
vote
1answer
131 views

Slow manipulation of netfilter rules

I have a script maintaining gre tunnels and firewall rules using the "ip" and "iptables" tools. Setting up hundreds of tunnels, and adresses per interface runs just fine. Takes less than 0.1 second ...
1
vote
2answers
376 views

download ip_tables kernel module

My linux system does not have the ip_tables kernel module, which I need for the openvpn server (for nat to work). Where can I download the source or binaries for that kernel module so I can modprobe ...