SDM Questions

Question 1

Which statement about the use of SDM templates in a Cisco switch is true?

A. SDM templates are used to configure system resources in the switch to optimize support for specific features, depending on how the switch is used in the network.
B. SDM templates are used to create Layer 3 interfaces (switch virtual interfaces) to permit hosts in one VLAN to communicate with hosts in another VLAN.
C. SDM templates are used to configure ACLs that protect networks and specific hosts from unnecessary or unwanted traffic.
D. SDM templates are used to configure a set of ACLs that allows the users to manage the flow of traffic handled by the route processor.
E. SDM templates are configured by accessing the switch using the web interface.

Answer: A

المصدر للشرح التالي هو سيسكو ويوجد المرجع لذلك أسف الشرح

Understanding the SDM Templates

You can use SDM templates to configure system resources in the switch to optimize support for specific features, depending on how the switch is used in the network. You can select a template to provide maximum system usage for some functions or use the default template to balance resources.

To allocate ternary content addressable memory (TCAM) resources for different usages, the switch SDM templates prioritize system resources to optimize support for certain features. You can select SDM templates to optimize these features:

  • Access—The access template maximizes system resources for access control lists (ACLs) to accommodate a large number of ACLs.
  • Default—The default template gives balance to all functions.
  • Routing—The routing template maximizes system resources for IPv4 unicast routing, typically required for a router or aggregator in the center of a network.
  • VLANs—The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

In addition, the dual IPv4 and IPv6 templates enable a dual stack environment. See the “Dual IPv4 and IPv6 SDM Templates” section.

There are two versions of each template: a desktop template and an aggregator template. The Catalyst 3750-12S switch can use the larger TCAM size available in the aggregator templates or can use the standard desktop templates. All other Catalyst 3750 switches support only the desktop templates. If you do not enter the desktop keyword on an aggregator switch, the aggregator templates are selected.

Reference: http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750/software/release/12-2_55_se/configuration/guide/scg3750/swsdm.html

Question 2

Which SDM template disables routing and supports the maximum number of unicast MAC addresses?

A. VLAN
B. access
C. default
D. routing

Answer: A

تجد الجواب في نفس شرح السؤال اﻷول وهو كما يلي:-

The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

Question 3

Which SDM template is the most appropriate for a Layer 2 switch that provides connectivity to a large number of clients?

A. VLAN
B. default
C. access
D. routing

Answer: A

نفس السؤال الثاني لكن مجرد تغيير في الصيغة

The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

Question 4

A network engineer deployed a switch that operates the LAN base feature set and decides to use the SDM VLAN template. The SDM template is causing the CPU of the switch to spike during peak working hours. What is the root cause of this issue?

A. The VLAN receives additional frames from neighboring switches.
B. The SDM VLAN template causes the MAC address-table to overflow.
C. The VLAN template disables routing in hardware.
D. The switch needs to be rebooted before the SDM template takes effect.

Answer: C

The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch only. But in this case this switch is also used for routing. The VLAN template disabled routing feature so all routing processing is sent to the CPU, seriously impacting switch performance, causing the CPU of the switch to spike, especially during peak hours.

Question 5

Which two statements about SDM templates are true? (Choose two)

A. They are used to allocate system resources
B. Changing the SDM template will not disturb switch operation.
C. You can verify the SDM template that is in use with the show sdm prefer command
D. SDM templates are defined by the switch model and cannot be changed
E. SDM templates changes do not require switch to be rebooted

Answer: A C

You can use SDM templates to configure system resources in the switch to optimize support for specific features, depending on how the switch is used in the network. You can select a template to provide maximum system usage for some functions; for example, use the default template to balance resources, and use access template to obtain maximum ACL usage. To allocate hardware resources for different usages, the switch SDM templates prioritize system resources to optimize support for certain features.
https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_53_se/configuration/guide/3750xscg/swsdm.html

Question 6

In a switch stack where is the the SDM template stored?

A. All switches in stack
B. Master switch
C. Flash memory

Answer: B

SDM Templates and Switch Stacks

In a Catalyst 3750-X-only or a mixed hardware switch stack, all stack members must use the same SDM desktop template that is stored on the stack master. When a new switch is added to a stack, the SDM configuration that is stored on the stack master overrides the template configured on an individual switch.

Question 7

What types of SDM templates you can use in switch? (Choose four)

A. Access
B. Default
C. Routing
D. VLANs
E. ?
F. ?

Answer: A B C D

سيكون في الختبار عناك خيارات بدل علامة اﻷستفهام لكن خيارات غير صحيحة

SDM templates are used to configure system resources in the switch to optimize support for specific features, depending on how the switch is used in the network. You can select a template to provide maximum system usage for some functions or use the default template to balance resources.

To allocate ternary content addressable memory (TCAM) resources for different usages, the switch SDM templates prioritize system resources to optimize support for certain features. You can select SDM templates to optimize these features:
Access – The access template maximizes system resources for access control lists (ACLs) to accommodate a large number of ACLs.
Default – The default template gives balance to all functions.
Routing – The routing template maximizes system resources for IPv4 unicast routing, typically required for a router or aggregator in the center of a network.
VLANs – The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

In addition, the dual IPv4 and IPv6 templates enable a dual stack environment.

Reference: http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750/software/release/12-2_55_se/configuration/guide/scg3750/swsdm.html

Question 8

Which three features can be optimized by using SDM templates? (Choose three)

A. port security
B. trunk
C. VLAN
D. access
E. DHCP snooping
F. routing

Answer: C D F

Question 9

When SDM templates are configured, which action must be performed for the configuration to take effect?

A. reload
B. shutdown
C. write memory
D. backup config

Answer: A

SDM Template Configuration Guidelines

  • When you configure a new SDM template, you must reload the switch for the configuration to take effect.
  • On switches running the IP base or IP services feature set, use the sdm prefer vlan global configuration command only on switches intended for Layer 2 switching with no routing.

When you use the VLAN template, no system resources are reserved for routing entries, and any routing is done through software. This overloads the CPU and severely degrades routing performance.

  • Do not select a routing template ( sdm prefer routing or sdm prefer dual-ipv4-and-ipv6 routing) when the switch is running the LAN base feature set. Although visible in the command-line help, the LAN base feature set does not support routing. On switches running the LAN base feature set, routing values shown in all templates are not valid.
  • Do not use the routing template if you do not have routing enabled on your switch. To prevent other features from using the memory allocated to unicast routing in the routing template, use the sdm prefer routing global configuration command.
  • If you try to configure IPv6 without first selecting a dual IPv4 and IPv6 template, a warning message appears.
  • Using the dual stack template results in less hardware capacity allowed for each resource, so do not use it if you plan to forward only IPv4 traffic.

    https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_53_se/configuration/guide/3750xscg/swsdm.html

Question 10

Which statement about the default Switch Database Management Template is true?

A. Template disables routing and supports the maximum number of unicast MAC addresses
B. Template maximizes system resources for access control lists
C. Template maximizes system resources for unicast routing
D. Template gives balance to all functions

Answer: D

To allocate ternary content addressable memory (TCAM) resources for different usages, the switch SDM templates prioritize system resources to optimize support for certain features. You can select SDM templates to optimize these features:

  • Access—The access template maximizes system resources for access control lists (ACLs) to accommodate a large number of ACLs.
  • Default—The default template gives balance to all functions.
  • Routing—The routing template maximizes system resources for IPv4 unicast routing, typically required for a router or aggregator in the center of a network.
  • VLANs—The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

Question 11

A question about a Layer 2 switch has been moved over to a Layer 2 and Layer 3 environment but high CPU spike during work hours.

A. show sdm prefer vlan
(config)# sdm prefer vlan
B. show sdm prefer routing
(config)# sdm prefer routing
C. show sdm prefer
(config)# sdm prefer routing
D. show sdm prefer
(config)# sdm prefer default

Answer: D

رأس السؤال قد يختلف في الأختبار لكن الجواب يتطلب أمرين احداهما لعرض نوع الـSDM واﻷمر اﻷخر لتعديله لذلك الجواب سيكون D

Question 12

Which statement about the default Switch Database Management template is true?

A. The default template disables routing and supports the maximum number of unicast MAC addresses.
B. The default template gives balance to all functions.
C. The default template maximizes system resources for unicast routing.
D. The default template maximizes system resources for access control lists.

Answer: B

الـــــشــــــــــــــــــــــــرح

You can select SDM templates to optimize these features:

  • Access—The access template maximizes system resources for access control lists (ACLs) to accommodate a large number of ACLs.
  • Default—The default template gives balance to all functions.
  • Routing—The routing template maximizes system resources for IPv4 unicast routing, typically required for a router or aggregator in the center of a network.
  • VLANs—The VLAN template disables routing and supports the maximum number of unicast MAC addresses. It would typically be selected for a Layer 2 switch.

Question 13

Which SDM command will provide maximum usage for IPv4 and IPv6 routing, including IPv4 policy-based routing on a switch?

A. sdm prefer dual-ipv4-and-ipv6 routing
B. sdm prefer dual-ipv4-and-ipv6 default
C. sdm prefer dual-ipv4-and-ipv6 vlan
D. sdm prefer dual-ipv4-and-ipv6 access

Answer: A

Setting the SDM Template

Beginning in privileged EXEC mode, follow these steps to configure an SDM template:

Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 sdm prefer { access | default | dual-ipv4-and-ipv6 { default | routing | vlan } | routing | vlan } Specify the SDM template to be used on the switch. The keywords have these meanings: access —Maximize system resources for ACLs. default —Give balance to all functions. dual-ipv4-and-ipv6 —Select a template that supports both IPv4 and IPv6 routing. – default —Balance IPv4 and IPv6 Layer 2 and Layer 3 functionality. – routing —Provide maximum usage for IPv4 and IPv6 routing, including IPv4 policy-based routing. – vlan —Provide maximum usage for IPv4 and IPv6 VLANs. routing —Maximize routing on the switch. vlan —Maximize VLAN configuration on the switch with no routing supported in hardware. Note Do not select a routing template when the switch is running the LAN base feature set. Although visible in the command-line help, the LAN base feature set does not support routing. Use the no sdm prefer command to reset the switch to the default desktop template. The default template balances the use of system resources.
Step 3 end Return to privileged EXEC mode.
Step 4 reload Reload the operating system.

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_53_se/configuration/guide/3750xscg/swsdm.html

Question 14

Which SDM command maximize routing on the switch?

A. sdm prefer routing
B. sdm prefer route-enabled
C. sdm prefer route-on
D. sdm prefer access-route

Answer: A

After the system reboots, you can use the show sdm prefer privileged EXEC command to verify the new template configuration. If you enter the show sdm prefer command before you enter the reload privileged EXEC command, the show sdm prefer command shows the template currently in use and the template that will become active after a reload.