Cisco "show running-config" Command Explained
show running-config — displays the active configuration in RAM — every setting currently in effect on the device. Runs in privileged EXEC mode.
Syntax and common variants
| Variant | Purpose |
|---|---|
show running-config | Entire active config |
show run interface gi0/1 | Just one interface's config |
show run | section ospf | Only the OSPF section |
show run | include hostname | Lines matching a word |
Reading the output
| Output field | Meaning |
|---|---|
(sections) | Config groups: interfaces, routing, lines, ACLs |
! | Separator between config sections |
building configuration… | The device assembling current state |
When to use it
The source of truth while troubleshooting: what is actually configured right now (versus what you assumed). Piping with | section and | include turns a long config into a targeted answer. Remember it lives in RAM — unsaved changes vanish on reload. Browse more in the command reference or practise in the free labs.
Frequently asked questions
What is the difference between running-config and startup-config?
running-config is the live config in RAM; startup-config is the saved copy in NVRAM used at boot. Save with copy run start.
How do I view just part of the config?
Pipe it: show run | section
Why don't I see passwords in the output?
Secrets appear hashed (enable secret) — and service password-encryption obscures line passwords.
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