5 ms·

Genuinely curious, is there an alternative to spanning tree? He'd mentioned not implementing it, but that feature is a life saver the 1% of the time that you ne

Genuinely curious, is there an alternative to spanning tree? He'd mentioned not implementing it, but that feature is a life saver the 1% of the time that you need it.

pas 10y ago
Manual configuration, or using iBGP (so you do L3 switching basically), see Project Calico, see what Facebook does (IP-IP encapsulation where the outer header is basically their L2 the switched fabric).
- hueving 10y ago
  >so you do L3 switching basically Ugh this term bothers me. Just call it routing! That hails from a day when routers sucked so much wind the marketing team at Cisco had to invent a new term for the stuff that did it fast.
  - pas 10y ago
    I usually call it routing, but I hoped OP would recognize the term.
- faded242 10y ago
  iBGP happens at L3, how is that going to stop a L2 loop exactly? There are plenty of alternatives to using spanning tree in a L2 network these days, you just have to have the right equipment to support it. There's TRILL, cisco's FabricPath (L2MP for everyone else).
  - pas 10y ago
    You disable L2 forwarding except to your iBGP link-local peers. Yes, I'd very much like to see TRILL gaining more widespread usage and attention, but fundamentally it's equivalent to IP-IP encapsulation plus IS-IS for link-state and iBGP for the outer IP layer, just with fancy terminology (RBridges and so on) and standardized administration/operational semantics. (Which is a good thing of course.)
technimad 10y ago
TRILL. Basically is-is applied at OSI Layer 2
wkz 10y ago
Shortest Path Bridging (802.1aq) Uses IS-IS to distribute the link-state db. And allows you to utilize an entire mesh, not just a sub-tree.
walrus01 10y ago
an alternative to spanning-tree? don't use it and don't try to extend layer 2 switch fabrics beyond a reasonable distance. things at unique geographical locations should not be able to ARP each other.
scurvy 10y ago
Layer 3 routing everywhere. No need for spanning tree. You've got things like VXLAN that can emulate layer 2 inside of layer 4 where necessary (mostly things like vmotion). I run several spanning-tree free networks and will never go back.

Genuinely curious, is there an alternative to spanning tree? He'd mentioned not implementing it, but that feature is a life saver the 1% of the time that you need it.

pas 10y ago

Manual configuration, or using iBGP (so you do L3 switching basically), see Project Calico, see what Facebook does (IP-IP encapsulation where the outer header is basically their L2 the switched fabric).

hueving 10y ago
>so you do L3 switching basically Ugh this term bothers me. Just call it routing! That hails from a day when routers sucked so much wind the marketing team at Cisco had to invent a new term for the stuff that did it fast.
- pas 10y ago
  I usually call it routing, but I hoped OP would recognize the term.
faded242 10y ago
iBGP happens at L3, how is that going to stop a L2 loop exactly? There are plenty of alternatives to using spanning tree in a L2 network these days, you just have to have the right equipment to support it. There's TRILL, cisco's FabricPath (L2MP for everyone else).
- pas 10y ago
  You disable L2 forwarding except to your iBGP link-local peers. Yes, I'd very much like to see TRILL gaining more widespread usage and attention, but fundamentally it's equivalent to IP-IP encapsulation plus IS-IS for link-state and iBGP for the outer IP layer, just with fancy terminology (RBridges and so on) and standardized administration/operational semantics. (Which is a good thing of course.)

technimad 10y ago

TRILL. Basically is-is applied at OSI Layer 2

wkz 10y ago

Shortest Path Bridging (802.1aq) Uses IS-IS to distribute the link-state db. And allows you to utilize an entire mesh, not just a sub-tree.

walrus01 10y ago

an alternative to spanning-tree? don't use it and don't try to extend layer 2 switch fabrics beyond a reasonable distance. things at unique geographical locations should not be able to ARP each other.

scurvy 10y ago

Layer 3 routing everywhere. No need for spanning tree. You've got things like VXLAN that can emulate layer 2 inside of layer 4 where necessary (mostly things like vmotion). I run several spanning-tree free networks and will never go back.