Andrew and Dennis are spot on. Their conclusions about your server being connected to an access port and not a trunk port would be my conclusion as well. On Sat, Jan 24, 2015 at 9:11 AM, Dennis Jacobfeuerborn < dennisml at conversis.de> wrote: > Hi Boris, > what I'd like to know is the actual VLAN configuration of the switch > port (link-type and tagged and untagged VLANs). When I look at the > switchport coniguration here I get (among other things): > > ... > Port link-type: trunk > Tagged VLAN ID : 8, 1624 > Untagged VLAN ID : 10 > ... > > Here is my suspicion: > Your ports have an access link-type with an untagged VLAN ID of 48. That > would explain why the moment you configure an IP from that VLAN on eth0 > you get connectivity because then the packets the Linux box sends are > untagged as the switch would expect them to be. If you only put an > address on eth0.48 then the packets get tagged by Linux but if the > switch port is not configured to receive the packets for VLAN 48 as > tagged then it will simply drop these packets and you will not get > connectivity. > Additionally, the switch should gripe about 802.1q BPDUs. Check the in-memory system log (or syslog server if you have configured that). show logging | i 1Q Example: 1w1d: %SPANTREE-2-RECV_1Q_NON_TRUNK: Received 802.1Q BPDU on non trunk FastEthernet0/2 on vlan 100. > > So getting the actual VLAN config of the switch port would help to > determine if the switch actually expects to receive the packets the way > you send them from the Linux box. > > +1 Let's see the config for the switch port your server is connected to. -- ---~~.~~--- Mike // SilverTip257 //