|Article Number: 532247||Article Version: 2||Article Type: Break Fix|
VxRack SDDC 14G-1
Dell S3048-ON management switch is not responding. Cumulus software 3.3 or above is installed on this switch.
Switch had been just installed as part of a new rack expansion and after a soft reboot customer was unable to connect back to it.
The management switch is unreachable via IP address from virtual machines or hosts
By default, Cumulus 3.3 and later reserves 1000 VLANs in the range of 3000-3999 to accommodate internal data plane operations. If VLANs have been defined in this range for any of the workload domains, networking issues will occur when attempting to communicate with the management switch from any of the VLANs that overlap from this range.
See also VMware KB https://kb.vmware.com/s/article/56517
To resolve this issue, complete the following steps:
#resv_vlan_range = 3000-3999
resv_vlan_range = 3700-3999
sudo systemctl restart switchd.service
The changes to the switchd.conf can also be completed using the following command:
sed -i "s/#resv_vlan_range = 3000-3999/resv_vlan_range = 3700-3999/g" /etc/cumulus/switchd.conf;reboot