Will loops occur when two network adapters of a server connect to a stack of S series fixed switches

To ensure reliability and service bandwidth, you are advised to take the following precautions when connecting two stacks of S series fixed switches. 1. Two or more cables are required to perform link backup, ensuring system reliability. 2. You are advised to connect the stacks with an even number of cables. 3. More cables connected can provide higher link bandwidths for transmitting services between the stacks.

After S series fixed switches set up a stack, they function as one switch on a network and do not affect the network services and functions. Stacks simplify the network management, and can also be associated with Eth-Trunks to improve network reliability and bandwidth usage.

To change the stack ID of an S series fixed switch (except the S1700 switch) of a stack, run the stack slot slot-id renumber new-slot-id command. Ensure that the new stack ID is unique in the stack. After changing the stack ID, restart the switch to make the setting take effect.

Stacking technology provides high network reliability and forwarding performance while simplifying network management. It has the following advantages: 1. High reliability: Member switches in a stack work in redundancy mode. Link redundancy can also be implemented between member switches through inter-device link aggregation. 2. High scalability: You can increase ports, bandwidth, and processing capacity of a stack by simply adding member switches to the stack. Member switches can join or leave the stack without affecting other member switches. New switches automatically synchronize the configuration file and system software version with the master switch. 3. Simpler configuration and management: You can log in to a stack from any member switch to manage and configure all the member switches in the stack. In addition, complicated Layer 2 ring protection protocols or Layer 3 protection switching protocols are not required after switches set up a stack; therefore, the network configuration is much simpler.

You can upgrade a stack of S series fixed switches using either of the following methods: Traditional upgrade: All member switches in the stack need to restart. This upgrade method causes service interruption in a relatively long time and can be used in scenarios insensitive to the service interruption time. Upgrade procedure 1. Upload system software to the master switch in the stack. 2. Run the startup system-software system-file all command to set the next startup software for all member switches in the stack. 3. Run the reboot command to upgrade the stack by restarting the entire system. Smooth upgrade: Member switches in a stack can be divided into an active area and a backup area that back up each other. Member switches in the two areas are upgraded in turn. During the upgrade of an area, traffic is transmitted through the other area, minimizing the impact of the upgrade on services. This upgrade method applies to scenarios sensitive to the service interruption time. The stack and networking must meet the following requirements: The uplinks and downlinks work in redundancy mode. The system software for next startup supports the smooth upgrade function. Member switches in the stack are running the same system software with the same software package name, version, and path. Member switches in the stack have the same system software for next startup with the same software package name, version, and path. Upgrade procedure 1. Upload system software to all the member switches in the stack. Ensure that member switches have the same system software with the same software package name, version, and path. 2. Run the system-view command to enter the system view. 3. Run the upgrade backup-area slot slot-id to slot-id command to define the active and backup areas for a smooth upgrade. The member switches with stack IDs in the specified range join the backup area, and the other member switches automatically join the active area. Note: Follow these rules to define the active and backup areas in a stack: The active and backup areas cannot contain the same member switch, and both areas must have at least one member switch. The backup area cannot contain the master switch. Member switches in each area must be directly connected. Member switches in the active and backup areas form the entire stack. 4. (Optional) Run the display upgrade area command to check whether the configured areas meet the requirements of the current stack topology. If the stack topology changes after the areas are configured, the smooth upgrade will fail. To avoid this problem, check the area configuration before starting a smooth upgrade. If the areas fail the check, redefine the active and backup areas correctly according to the current stack topology. 5. Run the upgrade start command to enable a smooth upgrade. 6. (Optional) Run the display upgrade state [ slot slot-id ] command to check the smooth upgrade status.