I'm not entirely sure about this:
<node id="network" claimed="true" class="network" handle="PCI:0000:08:00.0">
<description>Ethernet interface</description>
<product>RTL8125 2.5GbE Controller</product>
<vendor>Realtek Semiconductor Co., Ltd.</vendor>
<physid>0</physid>
<businfo>pci@0000:08:00.0</businfo>
<logicalname>eth0</logicalname>
<version>04</version>
<serial>[REMOVED]</serial>
<size units="bit/s">1000000000</size>
<capacity>1000000000</capacity>
<width units="bits">64</width>
<clock units="Hz">33000000</clock>
<configuration>
<setting id="autonegotiation" value="on" />
<setting id="broadcast" value="yes" />
<setting id="driver" value="r8125" />
<setting id="driverversion" value="9.003.05-NAPI" />
<setting id="duplex" value="full" />
<setting id="latency" value="0" />
<setting id="link" value="yes" />
<setting id="multicast" value="yes" />
<setting id="port" value="twisted pair" />
<setting id="slave" value="yes" />
<setting id="speed" value="1Gbit/s" />
</configuration>
<capabilities>
<capability id="pm" >Power Management</capability>
<capability id="msi" >Message Signalled Interrupts</capability>
<capability id="pciexpress" >PCI Express</capability>
<capability id="msix" >MSI-X</capability>
<capability id="vpd" >Vital Product Data</capability>
<capability id="bus_master" >bus mastering</capability>
<capability id="cap_list" >PCI capabilities listing</capability>
<capability id="ethernet" />
<capability id="physical" >Physical interface</capability>
<capability id="tp" >twisted pair</capability>
<capability id="10bt" >10Mbit/s</capability>
<capability id="10bt-fd" >10Mbit/s (full duplex)</capability>
<capability id="100bt" >100Mbit/s</capability>
<capability id="100bt-fd" >100Mbit/s (full duplex)</capability>
<capability id="1000bt-fd" >1Gbit/s (full duplex)</capability>
<capability id="autonegotiation" >Auto-negotiation</capability>
</capabilities>
<resources>
<resource type="irq" value="66" />
<resource type="ioport" value="c000(size=256)" />
<resource type="memory" value="fcc00000-fcc0ffff" />
<resource type="memory" value="fcc10000-fcc13fff" />
</resources>
</node>
Shuldn't there be a capability like "<capability id="2500bt-fd" >2,5Gbit/s (full duplex)</capability>"? So the support is there but "only" with 1 GBit/s FD?