Customers using vEdge SD-WAN appliances started experiencing a complete loss of service if their device was reloaded, updated, or when new templates were pushed.

The problem was caused by a cryptographic certificate, affecting the SD-WAN appliance's control plane which went into the underworld on 9 May.

“If left unaddressed, this could impact data plane connections and result in SD-WAN downtime,” Cisco said. 

The expiry could trigger networks using Cisco’s Viptela SD-WAN products for communication between their satellite offices, headquarters, and datacentres. While 

"All vEdge based SD-WAN customers are sitting on a time bomb, watching the clock with sweaty palms, waiting for their companies' WAN to implode and/or figuring out how to re-architect their WAN to maintain connectivity,"  one user moaned.

In addition to service disruptions, Cisco said organisations could experience:

• Loss of connections to vSmart and/or vManage
• Port-hopping tiggered
• Control policy changes down 
• Interface flapping
• Sweaty palms

As of publication, it appears Cisco has released a patch resolving the issue.

Danial Dib, a senior network architect at Cisco, shared a link to a software update for Cisco customers to address the disruption and said additional updates would be rolling out soon.