Customer complained on performance degradation when he changes media from auto to manual. We made RMA but the issue still exists. My tests tests were completed: copy/paste 200MB file via stupid cheap Dlink 100M switch path download/upload MByte/sec H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 10/10MB/s H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1<--SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 10/10MB/s H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/5MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 10/6MB/s H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 4/10MB/s H1<--SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 10/6MB/s Again H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/4MB/s Reboot SG1k H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/4MB/s Reboot SG1k H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 4/10MB/s Reboot SG1k H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/4MB/s H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/4MB/s Reboot H2 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/6MB/s Reboot SW1 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 4/6MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 6/6MB/s Reboot SG1k H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 10/10MB/s Hmmm... looks like something happens on sg1k and sw1 when I setup 100MFULL because only reboot both allowed to return to normal speed. Did not test manual 100MFULL and reboot will make tomorrow New test after 12 hours break (did nothing during break) H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/10MB/s H1<--SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 10/10MB/s H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/10MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 10/10MB/s H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 10/10MB/s Reboot sg1k H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1<--SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)<--H2 10/10MB/s H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 10/10MB/s H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 10/10MB/s H1<--SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 10/10MB/s unplug/plug both cables H1<--SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)<--H2 5/6MB/s dev.cpswss.0.stats.RxCrcErrors: 131 dev.cpswss.0.stats.RxAlignErrors: 216 H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 4/nMB/s dev.cpswss.0.stats.RxCrcErrors: 215 dev.cpswss.0.stats.RxAlignErrors: 420 H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/5MB/s dev.cpswss.0.stats.RxCrcErrors: 271 dev.cpswss.0.stats.RxAlignErrors: 532 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/5MB/s dev.cpswss.0.stats.RxCrcErrors: 311 dev.cpswss.0.stats.RxAlignErrors: 575 reboot sg1k and sw1 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/10MB/s no err H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/10MB/s no err H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/10MB/s no err unplug/plug WAN cable H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/9MB/s dev.cpswss.0.stats.RxCrcErrors: 26 dev.cpswss.0.stats.RxAlignErrors: 31 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/9MB/s dev.cpswss.0.stats.RxCrcErrors: 75 dev.cpswss.0.stats.RxAlignErrors: 57 reboot sw1 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/6MB/s dev.cpswss.0.stats.RxCrcErrors: 116 dev.cpswss.0.stats.RxAlignErrors: 98 reboot sg1k and sw1 H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/10MB/s no err unplug/plug WAN cable H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/10MB/s no err unplug/plug both cables H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(auto)-->H2 n/10MB/s no err set LAN to manual 100FULL H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/10MB/s no err unplug/plug LAN cable H1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/6MB/s dev.cpswss.0.stats.RxCrcErrors: 11 dev.cpswss.0.stats.RxAlignErrors: 37 Well, if port set to manual and cable is unpluged/pluged CRC and RXAlign errors start rising. Only both device sw and sg1k reboot helps. Continue testing with Cisco 3560 1-->SW1--(auto)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/10MB/s no err H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/10MB/s no err unplug/plug WAN cable H1-->SW1--(100FULL)-->WAN (NAT1:1)--SG1K--LAN--SW1--(100FULL)-->H2 n/0.5MB/s dev.cpswss.0.stats.RxCrcErrors: 1160 And Cisco shows 0 output errors, 36 collisions, 1 interface resets 0 babbles, 1163 late collision, 0 deferred Tried to setup manual on cisco port sg1k (still manual) - status: no carrier Changed to auto/auto on sg1k do not resolve issue Reboot sg1k resolve issue Looks like changing media to manual does not affect on real situation until cable is not upluged/pluged although ifconfig shows manual media selection. Anyway manual media selection does not work if device on another side uses manual too: sh run int fa0/14 interface FastEthernet0/14 switchport access vlan 15 switchport mode access speed 100 duplex full end sh int fa0/14 FastEthernet0/14 is down, line protocol is down (notconnect) cpsw1: flags=8843 metric 0 mtu 1500 options=8000b ether 68:9e:19:9c:9f:49 hwaddr 68:9e:19:9c:9f:49 inet6 fe80::6a9e:19ff:fe9c:9f49%cpsw1 prefixlen 64 scopeid 0x2 inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255 media: Ethernet 100baseTX status: no carrier nd6 options=21 And if another side device uses auto connection is negotiated as 100HALF sh int fa0/14 FastEthernet0/14 is up, line protocol is up (connected) Half-duplex, 100Mb/s, media type is 10/100BaseTX cpsw1: flags=8843 metric 0 mtu 1500 options=8000b ether 68:9e:19:9c:9f:49 hwaddr 68:9e:19:9c:9f:49 inet6 fe80::6a9e:19ff:fe9c:9f49%cpsw1 prefixlen 64 scopeid 0x2 inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255 media: Ethernet 100baseTX status: active nd6 options=21 looks like bug related to https://redmine.pfsense.org/issues/7532