Argentina Optical Path Switch Upgrade Version

Upgrading an Arista optical path switch involves selecting a compatible EOS version and following either a Smart System Upgrade (SSU) or standard upgrade procedure to minimize downtime and packet loss.Recommended Upgrade ApproachDetermine Target EOS Version Consult with your Arista Account or Systems Engineer to select the most suitable EOS version based on your network design, switch model, and operational requirements. Ensure the target version is MLAG ISSU compatible if the switch participates in an MLAG pair .Backup Current Configuration Before upgrading, copy the running configuration and current EOS image to the switch flash using the copy running-config command. Verify sufficient flash space for the new image and diagnostic files .Upgrade MethodsSmart System Upgrade (SSU): Ideal for minimizing downtime. SSU forwards packets in hardware while the control plane reloads, allowing near-hitless upgrades. For BGP or OSPF, perform a graceful restart to maintain routing stability .Standard Upgrade: Replace the EOS image and reload the switch. On redundant supervisor switches, install the image on both supervisors. This method is suitable for non-redundant switches or when SSU is not supported .MLAG ConsiderationsIf the switch is part of an MLAG pair, upgrade one peer at a time. Validate MLAG status and ensure all peerings and neighborships are active before upgrading the second peer .Orphaned hosts (single-homed) may experience traffic disruption during the upgrade.Upgrade Steps (Standard Procedure)Transfer the new EOS image to the switch flash.Modify the boot-config to point to the new image.Reload the switch and verify the new image is running.For MLAG devices, follow the intermediate version path if the current and target versions are not directly compatible .Post-Upgrade ValidationConfirm MLAG status, spanning-tree port states, and supervisor roles.Verify routing protocols and network services are fully operational.Key NotesAlways schedule a maintenance window to avoid business impact.Ensure serial console access is available in case of upgrade issues.For older EOS versions, contact Arista SE for image availability and support recommendations . Following these steps ensures a smooth, low-risk upgrade of your Argentina optical path switch while maintaining network stability and minimizing downtime.