14connection is allowed to be established. When the device functions as a Telnet client, use this keywordto define Telnet servers accessible to the client.Usage guidelinesIf no ACL is referenced in VTY user interface view, the VTY user interface has no access control overestablishing a Telnet or SSH connection.If an ACL is referenced in VTY user interface view, the connection is permitted to be established onlywhen packets for establishing a Telnet or SSH connection match a permit statement in the ACL.The system regards the basic/advanced ACL with the inbound keyword and the basic/advanced ACLwith the outbound keyword as different types of ACLs, which can coexist in one VTY user interface. Thematch order is basic/advanced ACL, Ethernet frame header ACL. At most one ACL of each type can bereferenced in the same VTY user interface, and the last configured one takes effect.For more information about ACL, see ACL and QoS Command Reference.Examples# Allow only the user with the IP address of 192.168.1.26 to access the device through Telnet or SSH. system-view[Sysname] acl number 2001[Sysname-acl-basic-2001] rule permit source 192.168.1.26 0[Sysname-acl-basic-2001] quit[Sysname] user-interface vty 0[Sysname-ui-vty0] acl 2001 inboundAfter the configuration, user A (with the IP address 192.168.1.26) can Telnet to the device, but user B (withthe IP address 192.168.1.60) cannot. Upon a connection failure, a message appears: "%connectionclosed by remote host!"# Allow the device to only Telnet to the Telnet server with IP address 192.168.1.41. system-view[Sysname] acl number 3001[Sysname-acl-adv-3001] rule permit tcp destination 192.168.1.41 0[Sysname-acl-adv-3001] quit[Sysname] user-interface vty 0 15[Sysname-ui-vty0-15] acl 3001 outbound[Sysname-ui-vty0-15] returnAfter your configuration, if you Telnet to 192.168.1.46, your operation fails. telnet 192.168.1.46%Can't access the host from this terminal!But you can Telnet to 192.168.1.41. telnet 192.168.1.41Trying 192.168.1.41 ...Press CTRL+K to abortConnected to 192.168.1.41 ...activation-keyUse activation-key to define a shortcut key for starting a terminal session.Use undo activation-key to restore the default.
