From a strictly physical cabling point of view, while 10GBaseT is likely to
work on ordinary cat5e or cat 6 cabling at very short distances such as
from a server to a top of rack aggregation switch, more successful results
will be seen with cat6a.Your typical cat 6A cable is significantly fatter in diameter, less
flexible and takes up much more space inside vertical cabling management
While some 6a are thicker than regular 5e thinner cables are available
for in rack use, such as
4.2mm 28AWG CAT6A
And even more space savings are
possible with single tube/uniboot, 1.6 mm diameter patch cables.
It is hard to compete with that but relaxing to cat6 and perhaps
dubious compliance there are even thinner 32AWG, while no use for POE
they are OK for the 2 or 3m needed in a rack
e.g. 2.8mm
https://www.amazon.co.uk/gp/product/B07Y3T6BYQ/
Also good for all the consoles/management ports which aren't fibre.
systimax cat6a is a general problem, I've done two building rewires
with Nexans Cat7a S/FTP where there was insufficient containment
space for systimax 6A.
brandon