0
votes
0answers
22 views

Force all traffic through VPN

I am using PfSense as a firewall, with its VPN functionality. The client I use is Shrew Soft VPN client. As it is a split tunnel, is there a way I can force all traffic through the VPN connection, ...
0
votes
2answers
50 views

IpTables Configuration Not Working to block ports (Centos 6.2)

I am trying to only allow certain IPs to access port 8209. I have tried a few different methods that I read on ServerFault. This method is the most recent one I have tried. I manually edited my ...
0
votes
1answer
42 views

Forward a port to another server using iptables

I have a server that is configured to block any port, and exceptions are configured like this (for mongo): iptables -A INPUT -p tcp --dport 27017 -s 10.20.1.0/8 -j ACCEPT ...
-2
votes
0answers
37 views

Difference between ipfw and iptables

I want to ask What is the difference between ipfw (FreeBSD) and iptables (Linux)? Can they do the same function? I am curious about this since I want to do actions similar to ipfw, but because I am ...
0
votes
1answer
21 views

change timeout for dropped ip traffic

I am behind a corporate firewall, which simply drops (swallows) all ip-traffic to unknown ip-addresses. It takes a lot of time for Linux (Ubuntu 13.10) to abort my erroneous connection-attempts, ...
0
votes
1answer
45 views

Turn IPTables Flush off CentOS

I made some changes to my iptables in a centOS machine. I noticed once I shut the server off it flushes all my iptables and goes back to the default. Is there a way to turn that off?
2
votes
1answer
42 views

connected to Centos openvpn but no outside internet access

I am using Windows 7 to connect to a VPS server running CentOS 6.4 First off, I have read every single post and just cant find the solution to my problem I configured my VPN server with openvpn, and ...
0
votes
1answer
56 views

Ubuntu 10.04LTS Server under attack, random reboots UNTIL I blocked China

What could have been sent to my server to cause it to reboot? Details: I have a for-internal-use LAMP server running Ubuntu 10.04LTS (upgrade is scheduled for that nebulous "when I have time"). It ...
0
votes
1answer
48 views

Configure atftp server to reply on port 69

Problem : I'm facing to a problem with TFTP server and Cisco 79XX IP phones. When on a local network, everything is working fine, but when the TFTP server is on a public server (and phones inside a ...
-1
votes
1answer
32 views

Firewall Connections fail to open under load

Problem : During High load , our applications are encountering errors : java.net.connection Time out. After some investigation , we found out that it was Firewall the root cause, but still don't know ...
4
votes
1answer
124 views

Why on linux machines, any packets do not pass except icmp, but correctly pass on windows

There is a cluster on proxmox. In a cluster have vm - configured router (pfsense). In the our net have Windows and Linux machines. There is the problem: Windows-machines have access to the internet, ...
0
votes
1answer
81 views

Point fail2ban to new log, without losing current bans?

I have logs in /var/log/syslog/YYYY-MM-DD/file.log files. New directories are created automatically by rsyslog, and logs are automatically put to new locations. Every day, I archive previous day of ...
1
vote
1answer
110 views

Is IGMP multicast traffic to a Xen VM host legitimate?

I run two Xen/CentOS 6.5 based VMs, both hosted by the same company, but connected to different networks (basic /24s w/ a single gateway at .1) in different physical locations. I developed an iptables ...
1
vote
3answers
345 views

iptables error: unknown option --dport

The command iptables no longer recognizes one of the most commonly used options when defining rules: --dport. I get this error: [root@dragonweyr /home/calyodelphi]# iptables -A INPUT --dport 7777 -j ...
1
vote
0answers
71 views

Vyatta Remote Access VPN firewall (PPTP)

I am using Vyatta Remote Access VPN (PPTP) and NAT for proxy. When pc-A and pc-B are connected to VPN, pc-A ipaddress is 192.168.10.10 and pc-B is 192.168.10.11. ...
3
votes
1answer
68 views

Smart solution for XenServer firewall?

I've been searching for a smart solution for a XenServer firewall for about a month now. The documentation for the new default networking backend "openvswitch" is not that detailed and I can barely ...
0
votes
1answer
88 views

iptables alternative for nat in windows

When setting up a comms server I usually use iptables in linux to forward any incoming connections on a particular port to another server, e.g. Chain PREROUTING (policy ACCEPT) target prot opt ...
0
votes
0answers
75 views

Dropping packets with Open Vswitch and OpenFlowControl

I am trying to setup some Flows with ovs-ofctl to block all unwanted incoming packets for a VM. The commands I use are: ovs-ofctl add-flow xenbr0 "priority=65000, table=0, tcp, dl_src=*, nw_src=*, ...
1
vote
1answer
80 views

Firewall rules using iptables using conditional statement

I have firewall rule that should accept all the connections, but drop connections from a ssh brute force attack (except 10.0.0.0/8 range). This rule will block an IP if it attempts more than 24 ...
0
votes
1answer
116 views

iptables DROP all access except my dynamic IP, is it possible and how/workaround?

If not possible, is there any workaround without affecting CPU performance? iptables -A INPUT -p tcp --dport 80 -j DROP
-1
votes
1answer
36 views

How to proxy to a web server on a node that can make outgoing connections but has no accessible IP, without root?

Not sure if this is the right StackExchange site to ask (I mainly frequent SO), but since you guys are server admin experts hopefully you'll find it relevant! Some context: I'm currently trying to ...
0
votes
1answer
64 views

Tool to allow Kerberos Authenticated users to modify Firewall settings

I run a firewall on a central router. Recently, several users want to use Skype. Since firewalling Skype virtually means to switch the firewall off, I consider to allow users to temporarily punch ...
0
votes
3answers
61 views

How do I stop someone from saturating my line & wasting CPU cycles

My web host shows inbound & outbound traffic with mrtg. I have a steady 3.5mbps inbound traffic from Nigeria. Even assuming the source IPs & destination ports are blocked with Iptables & ...
1
vote
1answer
212 views

How do I allow only certain IPSet set's to access a certain port with iptables?

I'm using IPSet to build IP ranges for different countries as follows : # Canada ipset -F ca.zone ipset -N ca.zone nethash for IP in $(wget -O - http://www.ipdeny.com/ipblocks/data/countries/ca.zone) ...
1
vote
0answers
148 views

Bypassing a transparent proxy using squid [closed]

I'm in a network where I can reach only one website for example exemple.com. Other requested web sites like google.com will be redirected to exemple.com, all other ports are work this way too ( in ...
1
vote
2answers
417 views

force LAN hosts to go through proxy

I have an IPTables firewall on a Debian server, with a bunch of hosts behind it with masquerading. In the upstream network I don't have direct access to the internet, and I need to go through a proxy ...
-3
votes
1answer
49 views

iptables allow A -> B:22 , B -> everywhere:22

I want iptables rules that let a server allow incoming ssh from a specific host and at the same time this server can connect ssh on any destination, then block any other in/out traffic Thanks in ...
0
votes
1answer
179 views

iptables Port Forwarding not working

I'm facing the problem, that my iptables rules aren't working anymore after I changed OS from Ubuntu 8.04 to Debian Squeeze. I'm trying to do a Port Forwarding by iptables -t nat -A PREROUTING -d ...
-1
votes
1answer
152 views

UFW rules for specific host / dynamic dns

How can I setup UFW (Uncomplicated Firewall) to add rules for specific hosts? Eg. I want to allow SSH only from yourpc.no-ip.org?
0
votes
0answers
110 views

APF (Advanced Policy Firewall) / iptables blocking seemingly legitimate traffic

I am running APF on my servers to handle both internal (eth0) and Internet (eth1) traffic. For the most part, everything is working correctly, but occasionally I see logs indicating that APF is ...
-1
votes
1answer
67 views

Is this CentOS 6.2 system reasonably secure as described? [closed]

This is a CentOS 6.2 system. For my login with the hosting company website, I set a 20-character mixed case, letters, numbers, symbols password and enabled two-factor authentication. In ...
1
vote
0answers
42 views

How can i manage bandwidht in linux router or firewall?

I have Linux server for internet sharing . i have 6 Mbps bandwidth, Now i want set 30Kbit to 40Kbit per user bandwidth. I want configure without proxy. It is possible that tc configration will ...
1
vote
1answer
96 views

How to ban 250.000 IP ranges?

I am using iblocklist.com and I want to ban a list of IPs I made from accessing my web server on a CentOS dedi. I have a bash script that can parse it and add the ranges one by one to iptables. My ...
0
votes
1answer
50 views

Can I put a linode instance behind our corporate firewall [closed]

I've built a little web application to collect internal survey data on a linode instance that I'd like to use in my company. My company already has windows servers set up that run intranet sites ...
0
votes
1answer
199 views

Why is UFW blocking some allowed internal connections?

My set up is this: Server 1 (192.168.1.1) - nginx (load balance) - Ubuntu 12.04 LTS Server 2 - uwsgi - Debian 7.1 Server 3 - uwsgi - Debian 7.1 UFW on server 2 and server 3, is blocking ...
0
votes
1answer
72 views

Iptables log clent IP to file

Im trying to track whether some ports are being used, and what by, as I want to close them. I have made some iptables traffic counters, and have worked out is a small amount of traffic, coming into a ...
0
votes
1answer
81 views

Memory usage on my firewall [duplicate]

I have a memory usage problem with my Checkpoint Firewall (it's a physical firewall). On my monitoring software OPManager I can see that 94% of my memory is used. In SSH, when i enter this command : ...
9
votes
3answers
249 views

advantages in closing a port where no services are running

Are there advantages in closing a port where no services are running? What do I gain in terminating a connection at iptables level instead of what does it next (I guess OS).
1
vote
2answers
171 views

How to establish firewall rules that accepting 11211 port in intranet for memcached ( Fedora)?

I am new for fedora and backend. And i have a job recently, to build a game server via linode. The current setup is 2 linode + 1 nodebalancer, I have a memcached server on each linode and I have setup ...
0
votes
3answers
372 views

Is there any logs in Linux which tells if some port has been denied

Suppose in i have the firewall active or any other security like SE linux etc. Now suppose user wants to connect to port 21 and Iptables does not allow it. Now when users gets denied is that ...
2
votes
2answers
135 views

Web Server Unable to Access from Internal Network

I have a web server that I am unable to access via its public IP address while I am on my internal network. If I am on an external network I can access the server via its public address. Also I am ...
4
votes
1answer
196 views

Configuring firewallD in Fedora 18/19

I am new to firewallD and have been going through the documentation but I thought maybe I can discuss some things here with everyone. So I see that firewalld has now replaced the iptables service as ...
0
votes
1answer
70 views

Get IP of the “requestor” when doing iptables NAT

I am doing NAT traffic forwarding using iptables (1.1.1.1 => 2.2.2.2) with the following commands: iptables -t nat -A PREROUTING -d 1.1.1.1 -j DNAT --to-destination 2.2.2.2 iptables -t nat -A ...
3
votes
1answer
845 views

How do I forward/NAT all traffic to one interface/IP to a remote IP?

I have one "server A" that has multiple IPs attached to it, like so: eth0:0 1.1.1.1 eth0:1 1.1.1.2 eth0:2 1.1.1.3 I have another "server B" that also has multiple IPs attached to it, like so: ...
-2
votes
2answers
101 views

Expose Azure linux vm to private network [closed]

I have a VM running linux in Microsoft Azure cloud, The VM is under Azure Virtual network and has a private IP and a public IP I wish to open all the ports (disable the firewall) for the VM only in ...
0
votes
1answer
71 views

Iptables to lock down compromised server to a single ip [duplicate]

I have a Linux server which is compromised, I can see nasty looking perl scripts executing with root privileges. I want to get some data off it before I wipe it. How can I block all inbound and ...
0
votes
1answer
50 views

why iptables giving error when using with --src-range

I am using iptables v 1.4.8 and used following command but getting one error message on terminal # iptables -A INPUT -m iprange --src-range 10.0.4.92-10.0.4.99 -j DROP modprobe: module 'ip_tables' ...
0
votes
2answers
137 views

Shorewall blacklist not working

We are getting dictionary attacks to our SQL server, So I wanted to block some of the IP's using shorewall blacklist. I mentioned the IP in /etc/shorewall/blacklist as #ADDRESS/SUBNET ...
-1
votes
1answer
124 views

iptables - how to improve security and allow dns? [closed]

I don't understand much about iptables, i'm running a server which is only used to run a vpn. Here's my iptables-save: # Generated by iptables-save v1.4.7 on Sat Jun 1 00:14:41 2013 *security ...
0
votes
1answer
44 views

Centralising IPTables rules?

When our collection of virtual servers got to a certain size, we moved from hosts files to a DNS server. However, we still have to update the firewall rules on every machine each time a new server is ...