Linux

4 Reasons Why SSH Connection Fails

As DevOps or IT professionals, people may ask us why they can’t ssh to servers. It happens from time to time. Isn’t right? Not much fun. Just routine work.

Want to ease the pain and burden? Let’s examine common ssh failures together. Next time forward this link to your colleagues, if useful. People may be able to identify the root cause all by themselves, or be efficient in collecting all necessary information, before turning to us.

Why SSH Connection Failed


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How To Check Linux Process Deeply With Common Sense

Apparently process checking is critical. Yes, we already have tons of linux tools and tips available. Getting familiar with your weapons is actually the first step, and the easiest part.

More importantly, what questions you ask, what for, when approaching your critical process. Fortunately even with plain common sense, we can dig out lots of valuable information.

Check Linux Process With Common Sense


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Shell Redirect Output To File, And Still Have It On Screen

Ever need to check the output of shell functions/scripts? If no fatal/error messages found, resume normal procedure. Otherwise, go to error handling.

Usually people solve this, by redirecting stdout/stderr to grep command. But What About Time-consuming Functions/Scripts? Say several minutes. During this period, end users are blinded with nothing printed. It could be confusing and scaring to them.

Linux Tee Command


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