Category Archives: Software

How to use OpenVPN over an IP over ICMP tunnel (Hans)

Introduction The very first question may is why to tunnel IP over ICMP at all? Sometimes you may find yourself in a situation where you have network, but no access to the Internet because of annoying restrictions. That f.ex. could be a proxy which requires authentication, a captive portal like in hotels or the ports you need simply are not … Continue reading

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Setup an OpenVPN server with certificate and two-factor authentication on CentOS 7

Introduction My goal was to have an OpenVPN server running, to which i can connect using different ports and by pipping it over an IP over ICMP tunnel (the latter will follow in another post). Ports i want to use: 1194/udp – The default OpenVPN port 53/udp – If im lucky and the network has DNS open by default… 1195/udp … Continue reading

Posted in CentOS, Firewalls, Linux, OpenVPN, Security, VPN | Tagged , , | 1 Comment

Quick tip: VMware vSphere and USB, use xHCI

For a project i had to move quite a lot of data, which is used as an initial seed for replication, to a second location. The best device i could find quickly was a 1TB USB disk. OK, fine… Copied all the data to the disk on my client and shipped the disk to the second location. There it was … Continue reading

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Increase SSL and TLS security on nginx and Apache by enabling PFS and HSTS

The default configuration of SSL is fine on most Linux distributions (you will get an A-Rating at SSL Labs), but still could be done a lot better and more secure. Goals we want to achieve: Enable Perfect Forward Secrecy (PFS) Enable HTTP Strict Transport Security (HSTS) Disable SSLv2 and SSLv3 PCI¬†compliant FIPS-ready¬†(optional) Don’t break IE… NOTE: the configuration below will … Continue reading

Posted in Apache, CentOS, Linux, nginx, Security | Tagged , , , , , , , , | 3 Comments

Change host name of Puppet client

Here are the steps i use to change the host name of a puppet client: On the client side stop Puppet, remove old certificates and change host name: Change the host name in /etc/sysconfig/network and /etc/hosts, then reboot the client. Remove the old certificate on the server: If you’re using Foreman, change the host name there too. Finally, initialize a … Continue reading

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