Source note · SIP TLS handshake failures on trunks
If the root or intermediate installed on the SBC is not the actual issuer chain of the SBC certificate, the Teams service cannot validate the chain and resets the connection; Microsoft lists this as a cause of an SBC that is intermittently inactive.
Checked 2026-09-25
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- certificate chain
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-25
- Checked
- 2026-09-25
Sources
- SBC connectivity issues — Microsoft · tier 2 current vendor documentation · SIP options issues > SBC status is intermittently inactive, second bullet
Cite this note
APA
WarmTransfer. (2026, September 25). SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-dr-chain-reset. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-chain-reset
BibTeX
@misc{warmtransfer-claim-sip-tls-handshake-failures-dr-chain-reset,
title = {SIP TLS handshake failures on trunks: source note sip-tls-handshake-failures-dr-chain-reset},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-tls-handshake-failures-dr-chain-reset},
note = {Source note sip-tls-handshake-failures-dr-chain-reset, checked 2026-09-25}
}