Debugging the BPF Virtual Machine Lorenzo Fontana October 28, 2020 ● Debugging is useful to understand how things work ● Sometimes, eBPF programs can’t even load ● I couldn’t find good resources on this this, so, here I am ● I break lots of eBPF programs ● The BPF Virtual machine is not easy to understand Why ? The BPF subsystem lives in the kernel AND The kernel can be debugged using gdb The

............................................................................ 161 8. Domain Name Service (DNS) .......................................................................................... program. The Live Server installer uses a text-based console interface which runs on the default virtual console. The interface can be entirely driven by the enter, up and down arrow keys (with some occasional Section 5, “Automatic Updates” [p. 34]. • Manage the system with Landscape: Landscape is a paid service provided by Canonical to help manage your Ubuntu machines. See the Landscape8 site for details.

install/netboot-arm64 arm64 netboot install 3 install/netboot-ppc64el ppc64el netboot install 3 install/ppc64el Virtual CDROM and Petitboot on ppc64el 1 Level Path Navlink 3 install/s390x-zvm s390x install via z/VM dump 2 OpenLDAP 3 service-ldap-introduction Introduction 3 service-ldap Installation 3 service-ldap-access-control Access control 3 service-ldap-replication Replication 3 service-ldap-usage Simple management 3 service-ldap-with-tls SSL/TLS 3 service-ldap-backup-restore Backup and restore 2 Kerberos 3 kerberos-introduction Introduction 3 service-kerberos Kerberos server 3 service-kerberos-principals

introduces the concept of the versatile-scenario OS, which achieves flexible version build and service composition through a full-stack atomization decoupling and Lego-style architecture, making it can continue managing processes on the host side. The DPUDirect feature significantly reduces service offloading costs in DPU scenarios, simplifies O&M, and significantly reduces subsequent maintenance management-plane processes offloaded to the DPU and the service processes on the host. In this way, applications are unaware of offloading. Only a small amount of service code on the management plane is needed to

administration tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1.6 Virtual consoles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1.3.8 Virtual filesystem of MC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 3.7.5 Customization example to tweak sshd service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 3.8 The udev system . . . .

Hardware Requirement Description Processor X86_64, > 1.5GHz Must choose 64bit X86 while using virtual machine Disk >= 50G System (25G), Docker Images(~5G), Linux Lab (20G) Memory >= 4G Lower than 4G Windows (include some older Windows 10) Docker Toolbox; Install Ubuntu via Virtualbox or Vmware Virtual Machine Before running Linux Lab, please refer to section 6.1.4 and make sure the following command command works without sudo and without any issue: 1 $ docker run hello-world In China, to use docker service normally, please must configure one of chinese docker mirror sites, for example: • Aliyun Docker

Hardware Requirement Description Processor X86_64, > 1.5GHz Must choose 64bit X86 while using virtual machine Disk >= 50G System (25G), Docker Images(~5G), Linux Lab (20G) Memory >= 4G Lower than 4G Windows (include some older Windows 10) Docker Toolbox; Install Ubuntu via Virtualbox or Vmware Virtual Machine Before running Linux Lab, please refer to section 6.1.4 and make sure the following command command works without sudo and without any issue: 1 $ docker run hello-world In China, to use docker service normally, please must configure one of chinese docker mirror sites, for example: • Aliyun Docker

Hubble can answer questions such as: Service dependencies & communication map What services are communicating with each other? How frequently? What does the service dependency graph look like? What HTTP HTTP calls are being made? What Kafka topics does a service consume from or produce to? Network monitoring & alerting Is any network communication failing? Why is communication failing? Is it DNS? Is it requests? Application monitoring What is the rate of 5xx or 4xx HTTP response codes for a particular service or across all clusters? What is the 95th and 99th percentile latency between HTTP requests and responses

Hubble can answer questions such as: Service dependencies & communication map What services are communicating with each other? How frequently? What does the service dependency graph look like? What HTTP HTTP calls are being made? What Kafka topics does a service consume from or produce to? Network monitoring & alerting Is any network communication failing? Why is communication failing? Is it DNS? Is it requests? Application monitoring What is the rate of 5xx or 4xx HTTP response codes for a particular service or across all clusters? What is the 95th and 99th percentile latency between HTTP requests and responses

Hubble can answer questions such as: Service dependencies & communication map What services are communicating with each other? How frequently? What does the service dependency graph look like? What HTTP HTTP calls are being made? What Kafka topics does a service consume from or produce to? Network monitoring & alerting Is any network communication failing? Why is communication failing? Is it DNS? Is it requests? Application monitoring What is the rate of 5xx or 4xx HTTP response codes for a particular service or across all clusters? What is the 95th and 99th percentile latency between HTTP requests and responses