Cisco Sg3008 Manual

							Administration: File Management
Auto Configuration via DHCP
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Auto Configuration via DHCPv4 is triggered in the following cases:
•After reboot when an IP address is allocated or renewed dynamically (using 
DHCPv4).
•Upon an explicit DHCPv4 renewal request and if the device and the server 
are configured to do so.
•Upon automatic renewal of the DHCPv4 lease.
Auto Configuration via DHCPv6 is triggered when the following conditions are 
fulfilled: 
•When a DHCPv6 server sends information to the device. This occurs in the 
following case s :
-When an interface, which is IPv6 enabled, is defined as a DHCPv6 
stateless configuration client. 
-When DHCPv6 messages are received from the server (for example, 
when you press the Restart button on IPv6 Interfaces page, 
-When DHCPv6 information is refreshed by the device. 
-After rebooting the device when stateless DHCPv6 client is enabled.
•When the DHCPv6 server packets contain the configuration filename 
option. 
DHCP Server Options
DHCP messages might contain the configuration server name/address and the 
configuration file name/path (these are optional options). These options are found 
in the Offer message coming from the DHCPv4 servers and in the Information 
Reply messages coming from DHCPv6 servers.
Backup information (configuration server name/address and configuration file 
name/path) can be configured in the Auto Configuration page. This information is 
used when the DHCPv4 message does not contain this information (but it is not 
used by DHCPv6). 
						

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Auto Configuration via DHCP
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Auto Configuration Download Protocol ( TFTP or SCP)
The Auto Configuration download protocol can be configured, as follows:
•Auto By File Extension—(Default) If this option is selected, a user-defined 
file extension indicates that files with this extension are downloaded using 
SCP (over SSH), while files with other extensions are downloaded using 
TFTP. For example, if the file extension specified is.xyz, files with the .xyz 
extension are downloaded using SCP, and files with the other extensions 
are downloaded using TFTP.
•TFTP Only—The download is done through TFTP regardless of the file 
extension of the configuration file name.
•SCP Only—The download is done through SCP (over SSH) regardless of 
the file extension of the configuration file name.
SSH Client Authentication Parameters 
By default, remote SSH server authentication is disabled, so that the device 
accepts any remote SSH server out of the box. You can enable remote SSH server 
authentication to only allow connections from servers found in the trusted server 
list. 
SSH Client Authentication parameters are required to access the SSH server by 
the client (which is the device). The default SSH Client authentication parameters 
are:
•SSH Authentication method: by username/password
•SSH username: anonymous
•SSH password: anonymous
NOTEThe SSH Client authentication parameters can also be used when downloading a 
file for manual download (a download that is not performed through the DHCP Auto 
Configuration feature). 
						

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Auto Configuration via DHCP
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Auto Configuration Process
When the Auto Configuration process is triggered, the following sequence of 
events occurs:
•The DHCP server is accessed to acquire the TFTP/SCP server name/
address and configuration file name/path (DHCPv4 options: 66,150, and 67, 
DHCPv6 options: 59 and 60). 
•If a server and configuration file options were not supplied by the DHCP 
server, then:
-For DHCPv4: The user-defined, backup configuration file name is used.
-For DHCPv6: The process is halted.
•If the DHCP server did not send these options and the backup TFTP/SCP 
server address parameter is empty then: 
-For DHCPv4:
SCP—The Auto Configuration process is halted.
TFTP—The device sends TFTP Request messages to a limited 
Broadcast address (for IPv4) or ALL NODES address (for IPv6) on its IP 
interfaces and continues the process of Auto Configuration with the first 
answering TFTP server.
-For DHCPv6: The Auto Configuration process is halted.
•If the configuration filename was supplied by the DHCP server (DHCPv4: 
option 67, DHCPv6: option 60), then the copy protocol (SCP/TFTP) is 
selected as described in Auto Configuration Download Protocol ( TFTP or 
SCP).
•When downloading using SCP, the device accepts any specified SCP/SSH 
server (without authentication) if either of the following is true:
-The SSH server authentication process is disabled. Note that by default 
the SSH server authentication is disabled in order to allow downloading 
configuration file for devices with factory default configuration (for 
example out-of-box devices).
-The SSH Server is configured in the SSH Trusted Servers list.
If the SSH server authentication process is enabled, and the SSH server is 
not found in the SSH Trusted Servers list, the Auto Configuration process is 
halted. 
						

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Auto Configuration via DHCP
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•I f  t h e  i n fo r m a t i o n  i s  av a i l a b l e ,  t h e  T F T P/ S C P  s e r v e r  i s  a c c e s s e d  to  d o w n l o a d  
the file from it.
The download process is done only if the new configuration filename is 
different from the current configuration filename (even if the current 
configuration file is empty).
•A SYSLOG message is generated acknowledging that the Auto 
Configuration process is completed.
Configuring DHCP Auto Configuration
Work flow
To configure DHCP Auto Configuration.
1. Configure the DHCPv4 and/or DHCPv6 servers to send the required options. 
this process is not described in this guide. 
2. Configure Auto Configuration parameters. 
3. Define the device as a DHCPv4 client in the Defining an IPv4 Interface in Layer 2 System Mode or Defining IPv4 Interface in Layer 3 System 
Mode  pages, and/or define the device as a DHCPv6 client in the 
IPv6 Interface page.
Web Configuration
The DHCP Auto Configuration page is used to perform the following actions when 
the information is not provided in a DHCP message:
•Enable the DHCP auto configuration feature.
•Specify the download protocol.
•Configure the device to receive configuration information from a specific file 
on a specific server.
Note the following regarding the DHCP auto configuration process:
•A configuration file that is placed on the TFTP/SCP server must match the 
form and format requirements of the supported configuration file. The form 
and format of the file are checked, but the validity of the configuration 
parameters is not checked prior to loading it to the Startup Configuration.
•In IPv4, to ensure that the device configuration functions as intended, due to 
allocation of different IP addresses with each DHCP renew cycle, it is 
recommended that IP addresses be bound to MAC addresses in the DHCP  
						

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Auto Configuration via DHCP
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server table. This ensures that each device has its own reserved IP address 
and other relevant information.
To configure auto configuration:
STEP 1Click Administration > File Management > DHCP Auto Configuration.
STEP  2Enter the values.
•Auto Configuration Via DHCP—Select this field to enable DHCP Auto 
Configuration. This feature is enabled by default, but can be disabled here.
•Download Protocol—Select one of the following options:
-
Auto By File Extension—Select to indicate that auto configuration uses 
the TFTP or SCP protocol depending on the extension of the 
configuration file. If this option is selected, the extension of the 
configuration file does not necessarily have to be given. If it is not given, 
the default extension is used (as indicated below).
-
File Extension for SCP—If Auto By File Extension is selected, you can 
indicate a file extension here. Any file with this extension is downloaded 
using SCP. If no extension is entered, the default file extension.scp is 
used.
-
TFTP Only—Select to indicate that only the TFTP protocol is to be used 
for auto configuration.
-
SCP Only— S ele ct to in dica te t hat onl y the S CP  proto c ol  is to b e us e d  for 
auto configuration.
•SSH Settings for SCP—When using SCP for downloading the configuration 
files, select one of the following options:
-
Remote SSH Server Authentication—Click on the Enable/Disable link to 
navigate to the SSH Server Authentication page. There you can enable 
authentication of the SSH server to be used for the download and enter 
the trusted SSH server if required.
-
SSH Client Authentication—Click on the System Credentials link to enter 
user credentials in the SSH User Authentication page.
STEP  3Enter the following optional information to be used if no configuration file name 
was received from the DHCP server. 
•Backup Server Definition—Select By IP address or By name to configure 
the server. 
						

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•IP Version—Select whether an IPv4 or an IPv6 address is used.
•IPv6 Address Type—Select the IPv6 address type (if IPv6 is used). The 
options are:
-Link Local—The IPv6 address uniquely identifies hosts on a single 
network link. A link local address has a prefix of FE80, is not routable, and 
can be used for communication only on the local network. Only one link 
local address is supported. If a link local address exists on the interface, 
this entry replaces the address in the configuration.
-Global—The IPv6 address is a global Unicast IPV6 type that is visible and 
reachable from other networks. 
•Link Local Interface—Select the link local interface (if IPv6 is used) from the 
list. 
•Backup Server IP Address/Name—Enter the IP address or the name of the 
server to be used if no server IP address was specified in the DHCP 
message.
•Backup Configuration File Name—Enter the path and file name of the file to 
be used if no configuration file name was specified in the DHCP message. 
STEP  4Click Apply. The parameters are copied to the Running Configuration file. 
						

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Auto Configuration via DHCP
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Administration
This section describes how to view system information and configure various 
options on the device.
It covers the following topics:
•Device Models
•System Settings
•Console Settings (Autobaud Rate Support)
•Management Interface
•User Accounts
•Defining Idle Session Timeout
•Time Settings
•System Log
•File Management
•Routing Resources
•Health
•Diagnostics
•Discovery - Bonjour
•Discovery - LLDP
•Discovery - CDP
•Ping
•Traceroute 
						

							Administration
Device Models
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Device Models
All models can be fully managed through the web-based switch configuration 
utility.
In Layer 2 system mode, the device forwards packets as a VLAN-aware bridge. In 
Layer 3 system mode, the device performs both IPv4 routing and VLAN-aware 
bridging. 
When the device operates in Layer 3 system mode, the VLAN Rate Limit, and QoS 
policers are not operational. Other QoS Advanced mode features are operational.
NOTEThe following port conventions are used:
•GE is used for Gigabit Ethernet (10/100/1000) ports.
•FE is used for Fast Ethernet (10/100) ports.
The following table describes the various models, the number and type of ports 
on them and their PoE information.  
Model Name Product ID 
(PID)Description of Ports on Device Power 
Dedicated 
to PoENo. of 
Ports that 
Support 
PoE
SG300-10 SRW2008-K9 8 GE ports, and 2 special-purpose combo 
ports (GE/SFP)N/A N/A
SG300-10MP SRW2008MP
-K9 8 GE ports, and 2 special-purpose combo 
ports (GE/SFP)124W 8
SG300-10P SRW2008P-
K98 GE ports, and 2 special-purpose combo 
ports (GE/SFP)62W 8
SG300-20 SRW2016-K9 16 GE ports, and 4 special purpose ports - 
2 uplinks and 2 combo portsN/A N/A
SG300-28 SRW2024-K9 24 GE ports, and 4 special-purpose ports - 
2 uplinks and 2 combo-portsN/A N/A
SG300-28P SRW2024P-
K924 GE ports, and 4 special-purpose ports - 
2 uplinks and 2 combo-ports.180W 24
SG300-52 SRW2048-K9 48 GE ports, and 4 special-purpose ports - 
2 uplinks and 2 combo-ports N/A  N/A
SF300-08 SRW208-K9 8 FE ports.  N/A  N/A 
						

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Device Models
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SF302-08 SRW208G-
K98 FE ports plus 2 GE ports  N/A  N/A
SF302-08MP SRW208MP-
K98 FE ports plus 2 GE ports 124W  8
SF302-08P SRW208P-K9 8 FE ports plus 2 GE ports 62W 8
SG300-10PP SG300-10PP-
K98-Port 10/100 PoE Managed Switch 62W 8
SG300-10MPP SG300-
10MPP-K910-Port Gigabit PoE Managed Switch 124W 8
SF300-24 SRW224G4-
K924 FE ports plus 4 GE special-purpose 
ports - 2 uplinks and 2 combo-ports.N/A N/A
SF300-24P SRW224G4P
-K924 FE ports plus 4 GE special-purpose 
ports - 2 uplinks and 2 combo-ports.180W 24
SF300-24PP SF300-24PP-
K924-Port 10/100 PoE Managed Switch 180W 24
SG300-28PP SG300-
28PP-K928-Port Gigabit PoE Managed Switch 180W 24
SF300-48 SRW248G4-
K948 FE ports plus 4 GE special-purpose 
ports - 2 uplinks and 2 combo-portsN/A N/A
SF300-48P SRW248G4P
-K948 FE ports plus 4 GE special-purpose 
ports - 2 uplinks and 2 combo-ports375W 48
SF300-48PP SF300-48PP-
K948-Port 10/100 PoE Managed Switch 375W 48
SG300-52MP SG300-
52MP-K952-Port Gigabit PoE Managed Switch 740W 48
SG300-10SFP SG300-
10SFP-K910-Port Gigabit Managed SFP Switch N/A N/A
SF300-24MP SF300-24M-
K924-Port 10/100 PoE Managed Switch 375W 24
SG300-28MP SRW2024P-
K928-Port Gigabit PoE Managed Switch 375W 24 Model Name Product ID 
(PID)Description of Ports on Device Power 
Dedicated 
to PoENo. of 
Ports that 
Support 
PoE