In order to test our deployment I want to simulate certain network events like connection losses, timeout, limited bandwidths etc.
I already googled for this but haven't found something that really suited my needs. ipfw seems to be what I need but I can't seem to find an ipfw package for Ubuntu. Also I'd like to know whether there are alternatives or even better tools for my task.
You can simulate those things with firewall.
Userland tool to modify firewall rules is called
iptables
for example if you want to simulate 5 seconds of connection loss you can do this
iptables -I INPUT -p tcp -s source.ip.for.which.you.want.to.appear.to.timeout --dpor $port -j DROP ;
sleep 5;
iptables -D INPUT -p tcp -s source.ip.for.which.you.want.to.appear.to.timeout --dpor $port -j DROP ;
iptables is great, but some tools are sharper when dealing with this kind of problems.
And also wanem, not a standalone app but more a customized router distro.
From the sister site Stack Overflow: Simulate delayed and dropped packets on Linux