strace - to see what a program is doing / where exactly something is failing if the error message is bad ltrace - same as above, if strace is not enough perf

strace - to see what a program is doing / where exactly something is failing if the error message is bad ltrace - same as above, if strace is not enough perf trace - if you don't know the exact process to strace upfront https://github.com/brendangregg/perf-tools https://github.com/brendangregg/perf-tools - to track disk accesses or exec calls env LD_DEBUG=all - debugging dynamic linker issues