Mini Container Series Part 0

Not a Real Container

Summary Recently, I learned some container technologies in Linux such as namespace and cgroup. However, after reading several articles and man pages, there was still one question lingering in my head - “How are the technologies put together?” In other words, how are they used to implement containers? [Read More]

Why doesn't traceroute work for ILA IP?

Summary Our project uses Identifier-Locator Addressing (ILA) for IPv6. Recently, we noticed that traceroute doesn’t work well for SIR address. The problem is, though traceroute can reach ILA router and eventualy reach the ILA host, all the intermediate nodes between the ILA router and the ILA host are shown as... [Read More]
Tags: ILA Network

Tcpkill for IPv6

Tcpkill tcpkill is part of dsniff, a collection of tools for network auditing and penetration testing. It can be used to kill specified in-progress TCP connections. [Read More]
Tags: Network TCP

Use bpftrace for debugging - An example

Introduction bpftrace is a high-level tracing language for Linux enhanced Berkeley Packet Filter (eBPF). I found it very useful for debugging issues as well as understanding kernel code. In this post, I will use one example to demonstrate how I used bpftrace for debugging. [Read More]
Tags: BPF

An Invalid bpf_context Access Bug

I got an interesting issue while debugging a BPF program. The BPF program couldn’t be loaded because of an “invalid memory access” error. Though the access was completely within the valid memory boundary, the verifier was still not happy about it. [Read More]
Tags: Linux BPF