When trying to add bgpAdvertisements with aggregationLengthV6: 128 it is taking default length as 32. Please check below error:
Error: "Error from server (invalid bgpadvertisement config: invalid aggregation length 32: prefix 128 in this pool is more specific than the aggregation length for addresses 2405:200:5f02:1:2333::8/128): error when applying patch:
{"metadata":{"annotations":{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"metallb.io/v1beta1\",\"kind\":\"AddressPool\",\"metadata\":{\"annotations\":{},\"name\":\"lb-signalling\",\"namespace\":\"metallb-system\"},\"spec\":{\"addresses\":[\"2405:200:5f02:1:2333::1/128\",\"2405:200:5f02:1:2333::2/128\",\"2405:200:5f02:1:2333::3/128\",\"2405:200:5f02:1:2333::4/128\",\"2405:200:5f02:1:2333::5/128\",\"2405:200:5f02:1:2333::6/128\",\"2405:200:5f02:1:2333::7/128\",\"2405:200:5f02:1:2333::8/128\"],\"autoAssign\":false,\"bgpAdvertisements\":[{\"aggregationLengthV6\":128,\"communities\":[\"64577:2333\"]}],\"protocol\":\"bgp\"}}\n"}},"spec":{"addresses":["2405:200:5f02:1:2333::1/128","2405:200:5f02:1:2333::2/128","2405:200:5f02:1:2333::3/128","2405:200:5f02:1:2333::4/128","2405:200:5f02:1:2333::5/128","2405:200:5f02:1:2333::6/128","2405:200:5f02:1:2333::7/128","2405:200:5f02:1:2333::8/128"],"bgpAdvertisements":[{"aggregationLengthV6":128,"communities":["64577:2333"]}]}}
to:
Resource: "metallb.io/v1beta1, Resource=addresspools", GroupVersionKind: "metallb.io/v1beta1, Kind=AddressPool"
Name: "lb-signalling", Namespace: "metallb-system"
for: "sigipv6.yaml": admission webhook "addresspoolvalidationwebhook.metallb.io" denied the request: invalid bgpadvertisement config: invalid aggregation length 32: prefix 128 in this pool is more specific than the aggregation length for addresses 2405:200:5f02:1:2333::8/128
"

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