это для 254, но лучше просто посмотри глазами, есть там портсек или нет и что он учит
DGS-3627G:4#show port_security
Command: show port_security
Port Admin State Max. Learning Addr. Lock Address Mode
----- ----------- ------------------- -----------------
1 Disabled 1 DeleteOnReset
2 Disabled 1 DeleteOnReset
3 Disabled 1 DeleteOnReset
4 Disabled 1 DeleteOnReset
5 Disabled 1 DeleteOnReset
6 Disabled 1 DeleteOnReset
7 Disabled 1 DeleteOnReset
8 Disabled 1 DeleteOnReset
9 Disabled 1 DeleteOnReset
10 Disabled 1 DeleteOnReset
11 Disabled 1 DeleteOnReset
12 Disabled 1 DeleteOnReset
13 Disabled 1 DeleteOnReset
14 Disabled 1 DeleteOnReset
15 Disabled 1 DeleteOnReset
16 Disabled 1 DeleteOnReset
17 Disabled 1 DeleteOnReset
18 Disabled 1 DeleteOnReset
19 Disabled 1 DeleteOnReset
20 Disabled 1 DeleteOnReset
21 Disabled 1 DeleteOnReset
22 Disabled 1 DeleteOnReset
23 Disabled 1 DeleteOnReset
24 Disabled 1 DeleteOnReset
25 Disabled 1 DeleteOnReset
26 Disabled 1 DeleteOnReset
27 Disabled 1 DeleteOnReset