HP StorageWorks 8/80 HP StorageWorks Fabric OS 6.1.x administrator guide (5697 - Page 92

Configuring the Telnet protocol Telnet is enabled by default. To prevent users from passing clear text passwords over the network when they connect to the switch, you can block the Telnet protocol using an IP Filter policy. NOTE: Before blocking Telnet, make sure you have an alternate method of establishing a connection with the switch. Blocking Telnet To block Telnet: 1. Connect to the switch and log in as admin. Connect through some means other than Telnet: for example, through SSH. 2. Create a policy: ipfilter --create -type < ipv4 | ipv6 > where is the name of the new policy and -type specifies an IPv4 or IPv6 address. Example ipfilter --create block_telnet_v4 --type ipv4 3. Add a rule to the policy, by typing the following command: ipfilter --addrule -rule -sip -dp -proto -act where -sip option can be given as any, dp is the port number for telnet (23), and -proto is tcp. Example ipfilter --addrule block_telnet_v4 -rule 2 -sip any -dp 23 -proto tcp -act deny 4. Save the new ipfilter policy by typing the following command: ipfilter --save [policyname] where [policyname] is the name of the policy and is optional. Example ipfilter --save block_telnet_v4 5. Activate the new ipfilter policy by typing the following command: ipfilter --activate where is the name of the policy you created in step Example ipfilter --activate block_telnet_v4 Unblocking Telnet To unblock Telnet: 1. Connect to the switch through a means other than Telnet (for example, SSH) and log in as admin. 2. Type in the following command: ipfilter -delete where is the name of the Telnet policy. 3. To permanently delete the policy, type the following command: ipfilter --save For more information on IP Filter policies, refer to "Configuring advanced security features" on page 105. 92 Configuring standard security features