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This is the support site for Andrews & Arnold Ltd, a UK Internet provider. Information on these pages is generally for our customers but may be useful to others, enjoy!

FireBrick SFP: Difference between revisions

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==TL;DR==
Regarding the SFPs, the short version is almost any copper SFP should
work for the FB2900, but there are a few silly types that don't. Yours
looks like it should just work.
 
==More Information==
 
The longer version for a bit more context:
 
Most SFPs have a little ROM chip inside them with make/model etc, and
most vendors use this to lock you into their own SFPs, ie Cisco switches
paired up with specific Cisco SFPs on a whitelist. They probably do this
for a reason, but it's really annoying, especially when you think you've
got an SFP, plug it in, only to find the switch rejects it as it's not
the "right" one.
 
The Firebrick 2900 is a bit more pleasant and actually doesn't really
care what's in the EEPROM as such, so you are free to use /almost/ any
SFP, provided the electrical connections are as expected.
 
For Copper SFPs, the FireBrick 2900 needs the "NO RX_LOS" hardware type,
which a majority are. This is down to how the SFP was wired with respect
to the LOS Pin. This is thankfully the most common type.
 
We've tested Flexoptix T.C12.02.A (Generic SFP flashed to have
it's EEPROM looking like a Cisco GLC-T) with the FB2900, but anything
that the T.C12.02.A can be flashed to should just work as they are all
electrically the same.
(See
https://www.flexoptix.net/en/sfp-copper-transceiver-1-gigabit-cat-5-rj-45-100m-autoneg-serdes.html?co3097=85155
for the various vendors and models it can do)
 
==RX_LOS Types Don't work==
 
Copper SFPs of the "RX_LOS" type don't work with the FB2900, such as the
Mikrotik S-RJ01 we tested. The Flexoptix T.C12.02 (note no .A appended)
and it's flashable derivatives will also be in this class. The RX_LOS
type are a bit of a daft class and I've never really got my head around
just why Flexoptix T.C12.02.Athey exist. Thankfully they're less common.
 
==Copper SFPs==
 
One final thing to bear in mind with a Copper SFP, is that they can only
negotiate a link at 1G, so the device plugging into them MUST support
Gigabit Ethernet. 10M and 100M are unsupported by the standard and will
not get you a link.
 
 
 
[[Category:FireBrick]]
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