Practical documentation and technical guides on network security, firewalls, Linux systems, monitoring, and automation.
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The Linux Network Namespace (netns) is a feature within the 2.6.27+ Linux kernel. Normally a Linux process will run within a network namespace. By default this is inherited from its parent process. Network namespaces allow for the process to run within a different network namespace. This allows for virtual instances of the Linux network stack … Read more
Today I will explain the concept of unpacking and packing within Python. Unpacking Unpacking allows us to pass keyword arguments (i.e dictionary) to a function via the use of the ** syntax. We can then access the values within the function like so, >>> def do_something(**kwargs): … print kwargs[‘a’] … print kwargs[‘b’] … print kwargs[‘c’] … Read more
Celery is an open source asynchronous task queue/job queue based on distributed message passing[1]. Within this article we will provide the configuration steps requiring for installing celery within Django. Our tutorial Example Broker Within this example we will use Redis as the broker. Celery uses a broker to pass messages between your application and Celery … Read more
Introduction Within this article we will provide the steps required to build a simple Neutron network. The network will consist of, Provider network (NET_EXTERNAL) Tenant network (NET_INTERNAL) L3 Router (NEUTRON-ROUTER) Floating IPs (172.16.100.30-172.16.100.70) Below is a diagram on how the topology looks, Provider Network First we create the provider network. This is a layer2 network … Read more
Within VMware there are 3 methods around VLAN tagging. They are EST, VST and VGT. Below shows the differences between the 3, Type Physical (VNIC) Virtual (vSwitch) EST Access port Access port VST Trunk port Access port VGT Trunk port Trunk port EST Within EST (External Switching Tagging) VLAN tags are not handled[1]. The physical switchport … Read more
Issue When creating a new instance within OpenStack you observe the following error, ==> /var/log/nova/nova-conductor.log <== … u”RescheduledException: Build of instance xxx-yyy-zzz was re-scheduled: internal error: no supported architecture for os type ‘hvm’\n”] … NoValidHost: No valid host was found. There are not enough hosts available. Solution This due to running OpenStack within a virtual … Read more
In order to interact with the F5 via Python the best option available is bigsuds. This is a Python module that allows you to interact with the F5 API iControl via a set of Python classes. Typically you will normally find all the methods you need to interact with your F5 without issues. However, there … Read more
Below are some of the most useful commands for the administration within the Gaia CLISH. show commands save config save the current configuration show commands shows all commands show allowed-client all show allowed clients show arp dynamic all displays the dynamic arp entries show arp proxy all shows proxy arp show arp static all displays … Read more
Introduction Within this article we will show you the steps needed to configure cookie persistence (insert) based on URI. i.e cookie persistence is only performed for a single URI. Cookie Insert When cookie insert persistence is configured the loadbalancer selects a server to the send the traffic to. The server id of the server is … Read more