I tried with Cisco Secure Client and OpenConnect: both gave me "login failed".
kc@KCs-Mac-Mini:/ % openconnect -v -v --protocol=anyconnect --user=kevink devnetsandbox-usw1-reservation.cisco.com:21140
POST https://devnetsandbox-usw1-reservation.cisco.com:21140/
Attempting to connect to server 131.226.217.48:21140
Connected to 131.226.217.48:21140
SSL negotiation with devnetsandbox-usw1-reservation.cisco.com
Connected to HTTPS on devnetsandbox-usw1-reservation.cisco.com with ciphersuite (TLS1.2)-(ECDHE-X25519)-(RSA-SHA256)-(AES-256-GCM)
Got HTTP response: HTTP/1.1 404 Not Found
Cache-Control: no-store
Pragma: no-cache
Connection: Close
Date: Tue, 24 Feb 2026 20:42:47 GMT
X-Frame-Options: SAMEORIGIN
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Content-Type-Options: nosniff
X-XSS-Protection: 1
Content-Security-Policy: default-src 'self' 'unsafe-inline' 'unsafe-eval' data: blob:; frame-ancestors 'self'; base-uri 'self'; block-all-mixed-content
Cross-Origin-Opener-Policy: same-origin-allow-popups
HTTP body http 1.0 (-1)
TLS/DTLS socket closed uncleanly
Unexpected 404 result from server
GET https://devnetsandbox-usw1-reservation.cisco.com:21140/
Attempting to connect to server 131.226.217.48:21140
Connected to 131.226.217.48:21140
SSL negotiation with devnetsandbox-usw1-reservation.cisco.com
Connected to HTTPS on devnetsandbox-usw1-reservation.cisco.com with ciphersuite (TLS1.2)-(ECDHE-X25519)-(RSA-SHA256)-(AES-256-GCM)
Got HTTP response: HTTP/1.0 302 Object Moved
Content-Type: text/html; charset=utf-8
Content-Length: 0
Cache-Control: no-store
Pragma: no-cache
Connection: Close
Date: Tue, 24 Feb 2026 20:42:48 GMT
X-Frame-Options: SAMEORIGIN
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Content-Type-Options: nosniff
X-XSS-Protection: 1
Content-Security-Policy: default-src 'self' 'unsafe-inline' 'unsafe-eval' data: blob:; frame-ancestors 'self'; base-uri 'self'; block-all-mixed-content
Cross-Origin-Opener-Policy: same-origin-allow-popups
Location: /+webvpn+/index.html
Set-Cookie: tg=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
HTTP body length: (0)
GET https://devnetsandbox-usw1-reservation.cisco.com:21140/+webvpn+/index.html
SSL negotiation with devnetsandbox-usw1-reservation.cisco.com
Connected to HTTPS on devnetsandbox-usw1-reservation.cisco.com with ciphersuite (TLS1.2)-(ECDHE-X25519)-(RSA-SHA256)-(AES-256-GCM)
Got HTTP response: HTTP/1.1 200 OK
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Content-Type-Options: nosniff
X-XSS-Protection: 1
Content-Security-Policy: default-src 'self' 'unsafe-inline' 'unsafe-eval' data: blob:; frame-ancestors 'self'; base-uri 'self'; block-all-mixed-content
X-Frame-Options: SAMEORIGIN
Cross-Origin-Opener-Policy: same-origin-allow-popups
Transfer-Encoding: chunked
Content-Type: text/xml; charset=utf-8
Cache-Control: no-store
Set-Cookie: webvpn=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpn_as=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpnc=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpnlogin=1; secure
X-Transcend-Version: 1
HTTP body chunked (-2)
Please enter your username and password.
GROUP: [SSLClient]:SSLClient
Please enter your username and password.
Password:
POST https://devnetsandbox-usw1-reservation.cisco.com:21140/+webvpn+/index.html
Got HTTP response: HTTP/1.1 200 OK
Strict-Transport-Security: max-age=31536000; includeSubDomains
X-Content-Type-Options: nosniff
X-XSS-Protection: 1
Content-Security-Policy: default-src 'self' 'unsafe-inline' 'unsafe-eval' data: blob:; frame-ancestors 'self'; base-uri 'self'; block-all-mixed-content
X-Frame-Options: SAMEORIGIN
Cross-Origin-Opener-Policy: same-origin-allow-popups
Transfer-Encoding: chunked
Content-Type: text/xml; charset=utf-8
Cache-Control: no-store
Set-Cookie: webvpn=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpn_as=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpnc=; expires=Thu, 01 Jan 1970 22:00:00 GMT; path=/; secure
Set-Cookie: webvpnlogin=1; secure
X-Transcend-Version: 1
HTTP body chunked (-2)
Login failed.
