D-Link DES-3528 Product Manual - Page 45

xStack® DES-3528/DES-3552 Series Layer 2 Stackable Fast Ethernet Managed Switch Web UI Reference Guide • There is no limit to the number of SIM groups in the same IP subnet (broadcast domain); however a single switch can only belong to one group. • If multiple VLANs are configured, the SIM group will only utilize the default VLAN on any switch. • SIM allows intermediate devices that do not support SIM. This enables the user to manage switches that are more than one hop away from the CS. The SIM group is a group of switches that are managed as a single entity. The Switch may take on three different roles: 1. Commander Switch (CS) - This is a switch that has been manually configured as the controlling device for a group, and takes on the following characteristics: a. It has an IP Address. b. It is not a command switch or member switch of another Single IP group. c. It is connected to the member switches through its management VLAN. 2. Member Switch (MS) - This is a switch that has joined a single IP group and is accessible from the CS, and it takes on the following characteristics: a. It is not a CS or MS of another IP group. b. It is connected to the CS through the CS management VLAN. 3. Candidate Switch (CaS) - This is a switch that is ready to join a SIM group but is not yet a member of the SIM group. The Candidate Switch may join the SIM group of the Switch by manually configuring it to be a MS of a SIM group. A switch configured as a CaS is not a member of a SIM group and will take on the following characteristics: a. It is not a CS or MS of another Single IP group. b. It is connected to the CS through the CS management VLAN The following rules also apply to the above roles: • Each device begins in a Candidate state. • CSs must change their role to CaS and then to MS, to become a MS of a SIM group. Thus, the CS cannot directly be converted to a MS. • The user can manually configure a CS to become a CaS. • A MS can become a CaS by: • Being configured as a CaS through the CS. • If report packets from the CS to the MS time out. • The user can manually configure a CaS to become a CS • The CaS can be configured through the CS to become a MS. After configuring one switch to operate as the CS of a SIM group, additionalDES-3528/DES-3552 Series switches may join the group by manually configuring the Switch to be a MS. The CS will then serve as the in band entry point for access to the MS. The CS's IP address will become the path to all MS's of the group and the CS's Administrator's password, and/or authentication will control access to all MS's of the SIM group. With SIM enabled, the applications in the CS will redirect the packet instead of executing the packets. The applications will decode the packet from the administrator, modify some data, and then send it to the MS. After execution, the CS may receive a response packet from the MS, which it will encode and send it back to the administrator. When a CaS becomes a MS, it automatically becomes a member of the first SNMP community (includes read/write and read only) to which the CS belongs. However, if a MS has its own IP address, it can belong to SNMP communities to which other switches in the group, including the CS, do not belong. 36