To be the best...

What are the top 3 traits or skills every system administrator must have to excel?

Can you suggest any tips or insights to develop your system administrator expertise?

I would say Networking, Servers and Security.

Networking: Knowing how LAN/WANs work and having the ability to Install, Configure and Troubleshoot Routers and Switches. A Cisco Certification like a CCNA (Cisco Certified Network Associate) is good to gave.

Servers: Knowing how to Set Up, Manage, Configure, Troubleshoot, Upgrade Servers. This is a very broad thing so which "type" of servers depends on the company. But a standard Microsoft Cert like MCSEA/MCSE or MCTS would be good to have.

Security: Security is a big concern so knowing how to secure your network, configure Firewalls, Monitor Network Traffic, IDS/IPS, etc... There are many certs for this, good one to have could be CEH (Certified Ethical Hacker).

Basically to be a System Administrator you have to somewhat be a "Jack of All Trades".

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