Alcatel Lucent OmniSwitch 6850 Stacking and Security Configuration Guide

Configuration Example (OSPF):

text

router ospf 1

area 0.0.0.0

interface vlan 10

ip ospf area 0.0.0.0

Troubleshooting:

OSPF neighbor cannot be established: check interface network type, hello/dead interval, authentication configuration.

Multicast not working: Check if IGMP snooping is enabled and if PIM mode matches.

Systematic positioning of common fault scenarios

8.1 Port unable to UP (copper/fiber optic)

Copper cable: First check the auto negotiation (default enabled), use TDR (Time Domain Reflectometry) to locate the cable breakpoint or short circuit point: TDR cable diagnostics interface gi 1/1/1, the system will return the distance and fault type (open circuit, short circuit, impedance abnormality).

Fiber optic: Check the recognition status of SFP module (show sfp), read DDM data (show sfp ddm), and check whether the optical power, temperature, and bias current exceed the limit. If the light attenuation is too large, clean the fiber optic connector or replace the module.

Protocol layer: If the port is err disable due to BPDU protection or loop detection, use errdisable recovery or manually shut down/no shutdown for recovery.

8.2 Stacking Splitting or Offline Members

Check the status of the stack link (show stack link). If a link is down, try unplugging the cable or replacing the SFP+module.

If there are two Primary members in the stack, you can manually specify the primary unit and restart the backup member to force the merge.

Check if there is a 'stack topology change' event in the system log (show log).

8.3 Abnormal PoE power supply

Check the total power usage (show poe), and if it exceeds the budget, the high priority port will automatically power off. Adjust port priority or add power modules.

If a single port is not powered, check if the port is configured with POE disable or if the powered device exceeds the maximum power of the port (default 15.4W).

Use LLDP to negotiate power requirements with devices.

8.4 Routing Protocol Neighbor Loss (OSPF/BGP)

Firstly, verify the physical link and IP connectivity (ping neighbors).

Check the VRF configuration (if multiple VRFs are enabled) and confirm that the interface belongs to the correct VRF.

For BGP, check the show BGP summary and if the neighbor status is Idle or Active, check if TCP port 179 is blocked by ACL.

Utilize BFD to quickly detect link faults.

8.5 Software upgrade failure or startup crash

The device flash stores dual images (primary/backup) and dual configuration files. If the new image cannot start, enter boot system backup rollback at the boot prompt.

If the device enters miniboot, the image can be reloaded through XMODEM or USB.

Before upgrading, be sure to back up the current configuration (copy running config) tftp://... ）And read the version release notes.

Characteristics of Metropolitan Ethernet

OmniSwitch 6850 supports IEEE 802.1ad (QinQ), ITU-T Y.1731 performance measurement, G.8032 ring network protection, and MAC Forced Forwarding (RFC 4562). It has been certified by MEF 9/14 and is suitable for operator access and metropolitan Ethernet services. During configuration, VLAN stacking and Service VLAN (SVLAN) mapping should be enabled, and DHCP Option 82 should be used to transmit user location information.