linux
nftables
Are you using the latest Linux kernel firewall?. Here are some notes I’ve saved that I use and forget all the time. I plan to add to this as I do more. Hopefully it helps you work something out one day. Note: I am using inet tables combining my IPv4 and IPv6 rulesets. List Tables […]
RPM vs OPKG Cheat Sheet
<p>Recently in the <a href="https://terragraph.com/">Terragraph</a> project I work on we changed from RPM to OPKG to removes some dependencies (e.g. perl) and make our overall image size smaller. I've never driven OPKG, but know RPM, so I made this cheat sheet for my shit memory.</p> <p>I'm cheap so I don't have a Table plugin – […]
IPv6 + Flow labels
Recently a teammate and I have come across a frame forwarding issue with ECMP on a hardware ASIC in a device I work on where the use of Flow labels are used in the ECMP hash. This was interesting as we found iperf was not setting the Flow label at all, unless you specify the -L […]
NXOS Simple IPv6 BGP Peering
It took me far to long to find out how to config this, so I’m sharing it to be more searching on the Internets. Scenario: – NXOS BGP ‘upsteam’ / ‘north bound’ peer sharing the default route only – Linux box runs Quagga sharing it’s /56 routable behind it Nexus Conf feature bgp router bgp […]
GitHub + Rebasing from upstream/master to origin/master
So, every now and then on a PR I need to rebase and fix things so I can retest etc. – I always forget this so blogging it to remember. Scenario: I have a diff on origin/master on my forked repo and I need a rebase from upstream/master (where I forked from). Process: Github recommends […]
IPv6 Tacacs+ Support (tac_plus)
Recently @ Facebook we found that we required IPv6 access to TACACS for auth (AAA) for the majority of our production Network Equipment. Tacacs+ (tac_plus) is an old daemon released by Cisco in the late 90s. It still works (even at our scale) and the config was doing what we required, so it was decided that we […]
IPERF CSV Data Summary Script
Recently I was required to do a network performance test between a Head Office and a WAN site. I knocked up this quick python script to parse the data collect to see the results. Thought it could be handy for others so here it is to download / share. Download Script Sample Output: [plain] cooper@dfbit:~/scripts/iperf-parse$ […]
Dennis Ritchie passes away …
The inventor of the C programming language and integral part of UNIX development has past away. RIP Dennis Ritchie. Thanks for the Uni lectures … BoingBoing Article
IPTables Template
So I thought I would share a good IPTables starting template, all tested on Ubuntu 10.10. [plain] # Cooper Lees IPTables Rules # Last Updated 20110409 # Drop by default iptables -P INPUT DROP iptables -A INPUT -i lo -j ACCEPT #ICMP is Good iptables -A INPUT -p icmp -j ACCEPT iptables -A INPUT -m […]
uit.sh Hits over 1000 Downloads !
Just thought I would pass on that my Ubuntu Iphone teathersing Shell Script has passed 1000 downloads. Feels good to have people all over the world use your script 🙂 Hope everyone that has downloaded it has enjoyed it as much as I have in the car on the way to work. To see my […]