Can clients connected to S series switch obtain IP addresses through DHCP

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DHCP-enabled terminals that are connected to S series switches except S1700 switches can obtain IP addresses from DHCP servers when either of the following conditions is met:
- The DHCP server function has been enabled on the switches. (By default, the DHCP server function is disabled on a switch.)
- A DHCP server is available on the network and reachable to the terminals.

Other related questions:
Can clients connected to S series switch obtain IP addresses through DHCP
DHCP-enabled terminals that are connected to S series switches except S1700 switches can obtain IP addresses from DHCP servers when either of the following conditions is met: - The DHCP server function has been enabled on the switches. (By default, the DHCP server function is disabled on a switch.) - A DHCP server is available on the network and reachable to the terminals.

Can terminals connected to S series switches obtain IP addresses through DHCP
For S series switches excluding the S1700, terminals connected to switches (enabled to obtain IP addresses through DHCP) can obtain IP addresses through DHCP when either of the following conditions is met: - The switch is configured with the DHCP server function. (By default, a switch is not configured with the DHCP server function.) - Another DHCP server is deployed on the network and there is a reachable route from the terminal to the DHCP server.

Types of packets checked by S series switches with IPSG enabled
For S series switches (except S1700 switches), IPSG takes effect only for IP packets (except DHCP packets) but not for packets of other types such as ARP or PPPoE. With IPSG enabled, an S series switch checks only IPv4 packets in versions earlier than V200R001 and checks all IPv4 and IPv6 packets in V200R001 and later versions.

Why does a user on an AR slowly obtain an IP address
The cause is that the interface is enabled with STP. By default, all interfaces of an AR are configured with STP. When the interface changes from Down to Up, STP convergence is performed (the process takes about 30s). During STP convergence, an interface on an AR directly discards received packets. That is, DHCP Request messages are all discarded during the STP convergence period. IP addresses are obtained slowly in this case. Use either of the following methods to solve this problem: - Run the stp edged-port enable command on the AR interface connected to a user terminal to configure the interface as an edge interface. If the AR is configured with the stp bpdu-protection command, the edge interface of the AR becomes Down when there are malicious attacks of BPDUs. To enable the edge interface to automatically go Up, run the error-down auto-recovery cause bpdu-protection interval interval-value command. - If there is no physical loop, run the stp disable command on the AR in the system view or the AR interface connected to a user terminal.

Long time to obtain IP addresses from S series switch
Users on S series switches except S1700 switches obtain IP addresses slowly because the STP function is enabled on interfaces of the switches. (By default, STP is enabled on all interfaces of a switch.) When an interface of a switch goes Up, STP convergence is performed for about 30 seconds. During STP convergence, the switch discards all received packets including DHCP request packets sent from users. As a result, the users obtain IP addresses slowly. You can resolve the problem using either of the following methods: - Run the stp edged-port enable command to configure the switch interface connected to users as an edge interface. If the stp bpdu-protection command has been configured on the switch, the edge interface of the switch goes Down when the switch receives attack BPDUs. To enable the edge interface to automatically go Up, run the error-down auto-recovery cause bpdu-protection interval interval-value command. - If no physical ring topology exists on the network, you can run the stp disable command on the switch globally or on the switch interface connected to users. Additionally, when the switch functions as a DHCP server and after you remove and reinstall the network cable, the PC obtains an IP address after 1 minute. The problem may be caused by a software bug. When you remove and reinstall the network cable, the PC sends DHCP Request messages to the DHCP server. In earlier versions of a switch, software cannot properly process this event.

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