This is using a Netgear Prosaft M4100-50G L2 switch. There are 2 VLANs on this switch, namely, vlan 10 besides 1. Ports 12, 21-35, 38-40, and 44 are on vlan 10. The rest is vlan 1. This switch is located in our remote office. There are 2 uplinks connected to this switch from our hq. The first uplink, connected to port 43, is basically uplink for vlan 1; second uplink, connected to port 24, is means for vlan 10. This logical segregation works perfectly, any port either belong to vlan 1 or 10, can grab the IP from respective dhcp servers located in hq.
2 week ago, thing changed. Users using vlan 1 ports found that they no more able to grab the IP. Their port looks like is entirely "isolated". After much checking, we were having a "workaround", that is, get in an additional 8-port switch, move the first uplink, and connect it to this 8-port switch. After that, get an additional short network cable, with one end connect to 8-port switch, and the other end to any vlan 1 port of this netgear switch. The vlan 1 operations are back to normal.
Just wondering why? How to get the netgear switch to work alone without this workaround?
Please see the netgear config as attached.
Thanks in advance.