It this certainly true that switches needs STP to avoid loops or broadcasts storms, but recently I saw the configuration of my Hewlett Packard switch and I noticed that it has STP feature disabled by default. Please could you explain this behavior? Answer in Spanish or English.

  • HP has spanning tree disabled by default, but you can certainly turn it on. As to why they made that decision, you'll have to ask them. Speculating on their reasons is off topic here.
    – Ron Trunk
    Mar 13 '20 at 21:37

Speculating why HPE does so is off-topic here, but there are a few reasons for disabling STP by factory default:

  • Ports go through their STP states between physical linking and active forwarding which may cause problems with DHCP and other protocols that expect an interface to actively work once it's up.
  • STP needs to be configured to work reliably and predictably - you need to select the best and most interoperable variant for your network: MSTP, RSTP, original (obsolete) STP or (R)PVST(+), and also which ones are your root switch and your designated root switch (lowest and second lowest priority values). MSTP instances require careful configuration as well.
  • The STP parameters themselves may require configuration for some networks, especially when long chains or rings are involved (large tree depth).
  • A newly configured STP bridge likely requires configuration of its downlink port - features like fast link and BPDU guard need to be disabled before connecting.

Disabling STP by default enables users to connect a new, unconfigured switch to a network like an unmanaged (dumb) one - which may be expected by less proficient users. More competent users configure a switch before integrating it in any case.

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