Tags » Iptables

SecureNet: Simulating a Secure Network with Mininet

I have been working with OpenStack(devstack) for a while and I must say it is quite convenient to bring up a test setup using devstack. At times, I still feel it is an overkill to use devstack for a quick test to verify your understanding of the network/security rules/routing etc. 1,119 more words


Ubuntu 16.06 Server Firewall (iptables), open port 80 and 443

apt-get install -y iptables-persistent

# Add netfilter-persistent Startup
invoke-rc.d netfilter-persistent save

# Stop netfilter-persistent Service
service netfilter-persistent stop

add the following lines in /etc/iptables/rules.v4

-A INPUT -p tcp -m state –state NEW,ESTABLISHED –dport 80 -j ACCEPT… 152 more words


How To Securely Open Ports (SSH, RDP etc.) On-Demand For Dynamic IPs Through iptables

An encrypted SSH connection allows complete access to your machine. However, unless you diligently manage all security updates to your OS and SSH Server, there is a possibility that your SSH server gets compromised. 428 more words


Iptables Rule Minimal for 'Secure' Server

Here is iptable rule minimal for ‘secure’ server,

iptables -A INPUT -m conntrack –ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -A INPUT -s 212.212.212.x/32 -p tcp -m tcp –dport 202 -j ACCEPT…

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Google Compute Engine (GCE) firewall and iptables at VM host

After I click “Allow HTTP” and “Allow HTTPS” in the settings of Centos 7 vm, I can get http or https pages of my site. What? 335 more words


SNMP unresponsive on Storage Cell after Exadata Patching

After a round of Exadata patching, the Storage Cells become unresponsive to SNMP for monitoring tools like OpsViews:

check_snmp_sysinfo CRITICAL - Agent not responding, tried SNMP v1 and v2c… 382 more words


Many users use IPTables in Linux as a firewall, and from a strict point of view, IPTables (IPTables 101) is just a command-line tool that helps administrators define rules and communicate with Linux Kernel. 185 more words

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