Dell Force10 MXL Manual 

Also see for Force10 MXL 10 GbE: Manual Getting started guide Deployment guide

Contents

Dell Force10 MXL Manual  Manual pdf 6 page image

Stacking Dell Force10 MXL 10/40G Switches4Additional stack members can immediately utilize existing configuration information such as routingand switching configurations, VLANs, ACLs, port profiles, and security certificates.RedundancyBy connecting a cable from the last switch in a stack back to the first switch, the operator ensures thata stack has the protection of redundant paths for control and data traffic. Support for link aggregationgroups (LAG) configured across multiple switches provides yet another layer of redundancy as well asadding bandwidth. This means that any single point of failure (a switch or a stack cable failure) will notaffect the overall operation of the remaining stack elements. This type of stacking topology is referredto as a “ring topology”. The other stacking topology where the last and first switch are not connectedis referred to as a daisy-chain topology stack. This type of stack is much less resilient and notrecommended in most cases. Both topologies are mentioned several times in this documentFailover rolesIf the stack Master fails (for example, loses power), it is removed from the stack topology. The Standbyunit detects the loss of peering communication and takes ownership of the stack management,switching from Standby to Master. If a Standby was not set up by the administrator, the stackautomatically triggers an election within the remaining units to select a new Master. While a newMaster is being selected (either through election or pre-selection), a new Standy is also chosen fromthe remaining members based on the same criteria as a Master selection (priority, then highest MACaddress).After the former Master switch recovers, despite having a higher priority or MAC address, it does notrecover its Master role but instead take the next available role as Standy or Member.Stacking LAGWhen multiple links between stack members are used, the Dell Force10 MXL automatically bundlesthem into a single logical link, or LAG, providing higher stacking bandwidth and redundancy. Thestacking LAG is established automatically without user configuration once all ports used in the LAG areset in stacking mode. The LAG can lose link or gain links simply by removing or inserting the cables.Enablement of LAG/LACP on blade serversAnother benefit of stacking MXL switches is that it allows a blade server to create LAGs to the stackedswitch. For example, if MXL switches are stacked in slots B1 and B2, then NICs on B1 and B2 on a givenserver could be configured for LAGs/LACP.Meta-dataThe actual stack configuration used to stack switches during power-up is read from meta-data, notfrom the startup configuration. It is applied at boot time prior to starting the switch firmware andreading the startup configuration. Stack information shown in the startup and running configurations issimply repeating information from the meta-data for the user’s knowledge. Therefore, if the startupconfiguration is deleted and the switch is reloaded, it will not clear the stacking configuration and thestack will remain intact after the reload. In order to remove the stacking configuration, the “no”command will need to be implemented for each of the stack-unit commands that were used to createthe stack.