STP looping problem

[Aso.Pere]

HI, I have a test environment and I am having a problem with time to time my ports are blocked by STP and then on again

I am wondering I am making a loop here or not, please refer to the diagram attached

This is my 2 swithes config
hostname "SW18"
time timezone
interface 1
exit
interface 15
speed-duplex auto-1000
exit
interface 24
speed-duplex 100-full
exit
ip default-gateway 10.9.135.2
logging facility local7

snmp-server community "public" Unrestricted
snmp-server community "xxxx" Operator Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged 17-24
ip address 10.9.135.18 255.255.255.0
no untagged 1-16
jumbo
exit
vlan 99
name "backup&ESX"
untagged 1-16
exit
management-vlan 1
spanning-tree
password manager
password operator





SW19# sh run

Running configuration:

; J9279A Configuration Editor; Created on release #Y.11.08

hostname "SW19"
time timezone
interface 19
speed-duplex auto-1000
exit
interface 24
speed-duplex 100-full
exit
ip default-gateway 10.9.135.2
logging facility local7
snmp-server community "public" Unrestricted
snmp-server community "xxx" Operator Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged 1-24
ip address 10.9.135.19 255.255.255.0
jumbo
exit
vlan 99
name "backup&ESX"
exit
management-vlan 1
spanning-tree

[Shadow13]

it depends if there is a topology change on your network due to some issues,

As a safe side you can configure all the edge ports connected to clients as admin-edge-ports and also bpdu-filter so that even if there is topology change client ports will not be blocked
#spanning-tree admin-edge-port
#spanning-tree bpdu-filter

Also please post the output of
#show spanning-tree