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firewall

HowTo: Linux Limit A Specific User’s Shell Account Network Bandwidth Using Bash Shell and Trickle

I am using a bash shell under Ubuntu Linux operating system. Sometime I need to restrict my own Internet bandwidth for all my shell applications such as ftp, sftp, wget, curl and friends. How do I limit the network speed under bash without setting up a complicated firewall and tc rules as described here?
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Sysadmin because even developers need heroes!!!

Verify: Keepalived IP Failover Working Or Not With tcpdump Command

I‘ve installed keepalived IP failover software as described here. But how do I verify it is working or not?
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BSD PF Firewall Block FTP Bruteforce Attacks

I see lots of failed FTP login attempts in my log file. How do I stop FTP bruteforce attack? What should I do to solve this problem under FreeBSD 7.x server operating systems?
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FreeBSD / OpeBSD Running in KVM Does Not Accept FTP Traffic

I‘ve setup FreeBSD and OpenBSD under KVM. Everything works great except ftp protocol. I’ve no firewall installed inside FreeBSD and OpenBSD. How do I configure Linux host KVM firewall to allow ftp traffic?
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I would like to tell my BSD based PF firewall to flush out the current configuration every 2 minutes. This will help me, when I’m testing a new rules and configuration options. Some time I find myself locked out of my own remote server. How do I reset PF firewall automatically without issuing hard reboot?
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FreeBSD Jail Access Private Network Via NAT and PF

I‘ve FreeBSD 7.x server with 3 jails are configured to run a mail, web and MySQL services. My FreeBSD box has two network interfaces. First, interface is connected to LAN and other is directly connected to the Internet via public IP. My DNS servers are hosted on private network (LAN). FreeBSD 7.x jail only support one interface and one IP address. How do I configure jail (FreeBSD vps) to access my DNS servers hosted inside my LAN using PF firewall?
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Iptables: Unblock / Delete an IP Address Listed in IPtables Tables

I am a brand new user of a Linux iptables and I can’t find how to instruct my iptables to delete or unblock an IP address listed in iptables firewall. I’m using Debian Linux version. Can you help please?
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BSD PF Firewall: Displays Active Packetfilter States And Rules

Q. How do I view active connections with PF firewall under FreeBSD / OpenBSD UNIX operating system?
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Access Any Remote Server Port Without Modifying Firewall Settings

Q. I’ve couple of remote servers and I’d like to access few admin only application running on port 10000 and 3001. My firewall only allows port 80, 443, 25, 22 and 110 for public access. Do I need to open port 10000 and 3001 for everyone using firewall? How do I access my admin only apps without opening port 10000 and 3001?
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OpenSuse / Suse Linux Open a Port Range in the Firewall

How do I open a network port range in the firewall under OpenSuse / Suse Enterprise Linux server? How do open a port range in my firewall, such as the TCP ports 30000 to 35000?
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