Archive for September 1st, 2013
Harley-Davidson – 110th Anniversary 1903-2013
Sonntag, September 1st, 2013Synology RackStation RS214 – is a 1U 2-bay rackmount NAS
Sonntag, September 1st, 2013Synology RackStation RS214 a 1U 2-bay rackmount NAS server with exceptional 287.5mm in depth offers an affordable and comprehensive solution for both industrial standard environments and smaller server rooms with limited space. Its compact size fits perfectly into 2-position rack and wall mount rack without additional rail kit. It is also resilient enough to withstand operating temperature up to 45°C offering high reliability under extreme conditions. The smart fan design keeps Synology RackStation RS214’s fan spinning at a very low Speed quiet your rack to create a calmer office working environment
Greenland’s ‚Grand Canyon‘ – a 460-mile-long stretch of canyon was discovered underneath ice
Sonntag, September 1st, 2013FreeBSD 9.1 – virtual wan simulator „WANsim“
Sonntag, September 1st, 2013For a experiment I needed a wan simulator so I decided to build one – using FreeBSD makes this very easy. Specifically what I wanted was a vmware virtual machine capable of Layer 2 wan Simulation it is easier because theres no routing or subnet changes to mess around with just simply a single subnet with some hosts further away than others. It had to be a VM as my whole lab environment is virtual so it makes sense to just put a vm between 2 vswitches and get the restricted bandwidth increased latency and packet loss
/etc/rc.conf
hostname=“WANsim“
keymap=“german.iso.kbd“
sshd_enable=“YES“
dumpdev=“AUTO“
#Bridge
cloned_interfaces=“bridge0″
ifconfig_bridge0=“addm em0 addm em1 up“
ifconfig_em0=“up“
ifconfig_em1=“up“
ifconfig_bridge0_alias0=“inet 192.168.1.253 netmask 255.255.255.0 up“
#Firewall
firewall_enable=“YES“
firewall_type=“open“
firewall_logging=“YES“
firewall_script=“/usr/local/etc/ipfw.rules“
/usr/local/etc/ipfw.rules
# delete all rules
# —————————————
ipfw -q -flush
# em0 3MBit/s and 20ms latency
# em1 0.5MBit/s and 20ms latency
# —————————————
ipfw -q add 10001 pipe 1 ip from any to any out via em0 bridged
ipfw -q add 10002 pipe 2 ip from any to any out via em1 bridged
ipfw -q pipe 1 config bw 3072Kbit/s delay 20
ipfw -q pipe 2 config bw 512Kbit/s delay 20
/etc/sysctl.conf
net.link.bridge.ipfw=1
/boot/loader.conf
if_bridge_load=“YES“
dummynet_load=“YES“
Placing the guest’s network adapter in promiscuous mode causes it to receive all frames passed on the virtual switch that are allowed under the VLAN policy for the associated portgroup