Since newer versions of Ubuntu like 20, you will find there is no longer dynagen and that the dynamips provided is faulty and will segfault each time: Cisco Router Simulation Platform (version 0.2.14-amd64/Linux stable) Copyright (c) 2005-2011 Christophe Fillot. Build date: Apr 3 2018 12:20:29 Local UUID: 3c1c0b7f-2fab-4fda-b40b-74841d1bcfe0 Instance ID set to 1. netio_tap_create: unable to open TAP device tap1 (No such fi........

This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525. Then nvidia-modeset goes to 100% There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines. https://forums.de........

You'll notice that /etc/resolv.conf contains dire warners on most Linux Desktops. # This file is managed by man:systemd-resolved(8). Do not edit. # # This is a dynamic resolv.conf file for connecting local clients to the # internal DNS stub resolver of systemd-resolved. This file lists all # configured search domains. # # Run "resolvectl status" to see details about the uplink DNS servers # currently in use........

Have you checked your router/firewall logs and disconcertingly see connections to an unknown IP207.246.119.209:3478 from your Grandstream VOIPphones? You're not alone and the Grandstream forums have discussed this issue. However, even their own staff d........

Kubernetes Easy Beginners Tutorial/Architecture Guide Kubernetes is known as container orchestration and we should start at explaining the container part of it. A Container is what runs the actual application and based on an Image, and are more comparable to something like an LXC Container, Virtuozzo/OpenVZ using the Linux Kernel Namespaces feature. Containers run these images as independent, isolated operating environments under the O........

This tutorial will get your router up and running using emulation tools. In this case we'll be getting a Cisco C7206 (C7200 series) VXR router going which also supports SCCP VOIP services. dynamips is the emulator itself and dynagen is the front-end tool that helps us control everything. It is used by tools such as gns3 and eve-ng. Together the two tools (dynamips and dynagen) allow us to create and emulate REAL router........

Just edit your tftp file for xinetd like this: *Change the IPto be the IPof the interface you want to listen on. To test if your tftp is available on a certain IP range use nc -u yourip 69 to see if you can still connect (/var/log/messages or /var/log/syslog) should show the connection if it is open. Oct 13 23:20:34 01 xinetd[26631]: Started working: 1 available servic........

#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2 tar -jxvf ffmpeg-3.3.2.tar.bz2 cd ffmpeg-3.3.2/ ./configure --disable-yasm install prefix /usr/local source path ........

Cannot even "Browse Network" when clicking on "Windows Network" Unable to mount location Failed to retrieve share list from server: No such file or directory logs: [2017/02/14 00:16:44.271314, 0] ../source3/nmbd/nmbd.c:58(terminate) Got SIGTERM: going down... [2017/02/13 17:35:41.797944, 0] ../lib/util/become_daemon.c:124(daemon_ready) &........

yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........

iptables -t nat -A PREROUTING -p udp -m multiport --dports 20,123,443 -j REDIRECT --to-port 53 getsockopt failed strangely: Invalid argument........

netstat is weak and can't show udp connections and most other protocols, use "ss" which is what netstat should have been: The "-u" switch stands for udp, here's a list of other options: Usage: ss [ OPTIONS ] ss [ OPTIONS ] [ FILTER ] -h, --help this message -V, --version output ver........

One thing to note about DNS servers and providers is that they aren't always trustworthy, not even if they're Google or your favorite ISP. Any DNS server can compromise your privacy, and they are likely tracking your browsing habits and keeping logs of it. Sometimes it's for Marketing/Research purposes such as Google's GMail service which they admit is scraped/datamined. I would expect nothing less from their DNS service. The other danger with such widely used and pu........

Basic Port ListingHopefully someone finds this useful or at least interesting. http://www.sans.org/top20/#u9 Name Port Protocol Description Small services ........

There's a lot of information and guides on OCFS2 for RHELand Centos Linux but the package setup and configuration is slightly different and this has thrown some people off. Installing OC2FS You should install the following packages to get started: apt-get install ocfs2-tools ocfs2console Configure OC2FS In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb However in Debian based Linux it is located........