Fortigate sslvpn issue 5.6.3

when you updated your firmware of fortigate or setup new sslvpn, if you are using certificate other than factory default you might have issue to connect to sslvpn

from fortigate debug:

Inovfw10 # [18907:root:fc]allocSSLConn:280 sconn 0x7f820714c000 (0:root)

[18907:root:fc]SSL state:before SSL initialization (208.98.207.34)

[18907:root:fc]SSL state:before SSL initialization:DH lib(208.98.207.34)

[18907:root:fc]SSL_accept failed, 5:(null)

[18907:root:fc]Destroy sconn 0x7f820714c000, connSize=0. (root)

[18907:root:fd]allocSSLConn:280 sconn 0x7f820714c000 (0:root)

[18907:root:fd]SSL state:before SSL initialization (208.98.207.34)

[18907:root:fd]SSL state:before SSL initialization (208.98.207.34)

[18907:root:fd]SSL state:fatal handshake failure (208.98.207.34)

[18907:root:fd]SSL state:error:(null)(208.98.207.34)

[18907:root:fd]SSL_accept failed, 1:no shared cipher

[18907:root:fd]Destroy sconn 0x7f820714c000, connSize=0. (root)

[18907:root:fe]allocSSLConn:280 sconn 0x7f820714c000 (0:root)

[18907:root:fe]SSL state:before SSL initialization (208.98.207.34)

[18907:root:fe]SSL state:before SSL initialization (208.98.207.34)

[18907:root:fe]SSL state:fatal handshake failure (208.98.207.34)

[18907:root:fe]SSL state:error:(null)(208.98.207.34)

[18907:root:fe]SSL_accept failed, 1:no shared cipher

[18907:root:fe]Destroy sconn 0x7f820714c000, connSize=0. (root)

The server you want to connect to requests identification, please choose a certificate and try again. (-5)

from Fortigate GUI:

gui vpn events:

Log Description SSL VPN exit error

Action	ssl-exit-error
Reason	N/A

solution:

conf vpn ssl settings

set algorithm medium