There is a question that I asked in AskUbuntu however I am starting to wonder if I might not find more accurate and specialist help in Unix and Linux. Is this an appropriate question to cross post or re-ask?
First of all, no question should ever be posted cross site (unless it clearly applies to many subjects that both sites support (in which case it is too specific anyway)). It creates spam. Is cross posting a question on multiple stack exchange sites permitted if the question is on-topic for each site?
This question specifically seems like a question based on Ubuntu alone, not other Linux or Unix systems, so Ask Ubuntu seems like the proper site.
There are a few exceptions, but if you must cross-post, you should tailor the post to each specific site. From the top answer to the linked question:
Occasionally, people are interested in different perspectives on the same fundamental question. There are many Stack Exchange sites with overlapping topic spaces, and it can be useful to get a "second opinion". Even then, however, it's best to tailor your question to each site. Ideally, you should link to the question on the other site and explain what you hope to learn from asking another community.