www.cisco.com is your friend.
From cisco.com, the relevant documents state the following with respect to stacking:
http://www.cisco.com/en/US/docs/swit...Series_QSG.pdf
"The 500 and 500X switches support the following SFP+ Copper Cable modules for stacking: SFP-H10GB-CU1M, SFP-H10GB-CU3M, and SFP-H10GB-CU5M."
http://www.cisco.com/en/US/prod/coll...ata_sheet.html
The data sheet states that the above mentioned cables are not included with the switch and therefore, you'll have to purchase them.
"Package Contents
• Cisco Small Business 500/500X Series Stackable Managed Switch
• Power cord
• Mounting kit included with all models
• Serial cable
• CD-ROM with user documentation (PDF) included
• Quick Start Guide "
The document below shows the various optic and cabling options:
http://www.cisco.com/en/US/prod/coll...c45-726838.pdf
Now for the technical discussion. Stacking switches has been around a while. Stack ports are dedicated ports used for the stack management and interswitch data traffic (ie if data has to flow between switches). These ports can be the standard data ports on the switch or they can be specific ports used only for stacking (these ports typically require specific custom cables). From the looks of the information, the cable used for the SG500 is a 10Gig DAC (direct attach cable) or sometimes referred as twinax. It also appears that the switch can also stack over 1Gig connections on the 1 Gig SFP ports. These cables are used for 10GigE connections between switches but apparently Cisco has created a non standard connection of 5Gig using these cables for your switches. What this means is you have a maximum of 10 Gig of bandwidth on the stacking connection between switches in the stack. This is pretty low and means the stack is oversubscribed 4.8:1. Many stack configurations I've seen range from 24 Gigs up to 64 Gigs (or more) of throughput over the stacking links. Also when you stack beyond 4 switches, you'll have to consider differences in the use of the standard ring and braided ring topologies.
While stacking creates one large virtual switch from multiple physical switches, a limitation to stacking is when you have to do firmware upgrades. As a requirement for stacking, all switches must run the same firmware code. When you upgrade one switch, you have to push the code to all member switches in the stack. And for the firmware to go into operation, the entire switch stack will need to be rebooted necessitating an outage. There are newer virtual switch technologies which eliminate or reduce this issue which go by names like MLAG, VLT, VCS, VSS, etc.
From cisco.com, the relevant documents state the following with respect to stacking:
http://www.cisco.com/en/US/docs/swit...Series_QSG.pdf
"The 500 and 500X switches support the following SFP+ Copper Cable modules for stacking: SFP-H10GB-CU1M, SFP-H10GB-CU3M, and SFP-H10GB-CU5M."
http://www.cisco.com/en/US/prod/coll...ata_sheet.html
The data sheet states that the above mentioned cables are not included with the switch and therefore, you'll have to purchase them.
"Package Contents
• Cisco Small Business 500/500X Series Stackable Managed Switch
• Power cord
• Mounting kit included with all models
• Serial cable
• CD-ROM with user documentation (PDF) included
• Quick Start Guide "
The document below shows the various optic and cabling options:
http://www.cisco.com/en/US/prod/coll...c45-726838.pdf
Now for the technical discussion. Stacking switches has been around a while. Stack ports are dedicated ports used for the stack management and interswitch data traffic (ie if data has to flow between switches). These ports can be the standard data ports on the switch or they can be specific ports used only for stacking (these ports typically require specific custom cables). From the looks of the information, the cable used for the SG500 is a 10Gig DAC (direct attach cable) or sometimes referred as twinax. It also appears that the switch can also stack over 1Gig connections on the 1 Gig SFP ports. These cables are used for 10GigE connections between switches but apparently Cisco has created a non standard connection of 5Gig using these cables for your switches. What this means is you have a maximum of 10 Gig of bandwidth on the stacking connection between switches in the stack. This is pretty low and means the stack is oversubscribed 4.8:1. Many stack configurations I've seen range from 24 Gigs up to 64 Gigs (or more) of throughput over the stacking links. Also when you stack beyond 4 switches, you'll have to consider differences in the use of the standard ring and braided ring topologies.
While stacking creates one large virtual switch from multiple physical switches, a limitation to stacking is when you have to do firmware upgrades. As a requirement for stacking, all switches must run the same firmware code. When you upgrade one switch, you have to push the code to all member switches in the stack. And for the firmware to go into operation, the entire switch stack will need to be rebooted necessitating an outage. There are newer virtual switch technologies which eliminate or reduce this issue which go by names like MLAG, VLT, VCS, VSS, etc.