Hello

A few days ago we ran into issue where the number of stunnel threads sky rocketed to over 3000 open stunnel threads. When this happen connections to our website slowed down considerably or failed to connect. It was resolved by flipping to our other proxy which accepted any new connections. It took about 5 minutes for the threads to die off on the other proxy. I was wondering if anyone has come across this problem?

Here are some details of our stunnel version and config.

Stunnel 4.44 with patch for x-forwarder

[root@brm-proxy01 ~]# stunnel -version stunnel 4.44 on x86_64-unknown-linux-gnu platform Compiled/running with OpenSSL 1.0.0-fips 29 Mar 2010 Threading:PTHREAD SSL:ENGINE Auth:LIBWRAP Sockets:POLL,IPv6

Global options: debug = daemon.notice pid = /var/run/stunnel.pid RNDbytes = 64 RNDfile = /dev/urandom RNDoverwrite = yes

Service-level options: ciphers = ALL:!SSLv2:!aNULL:!EXP:!LOW:-MEDIUM:RC4:+HIGH curve = prime256v1 session = 300 seconds sslVersion = TLSv1 for client, all for server stack = 65536 bytes TIMEOUTbusy = 300 seconds TIMEOUTclose = 60 seconds TIMEOUTconnect = 10 seconds TIMEOUTidle = 43200 seconds verify = none appriacated

Our stunnel.conf.

/etc/stunnel/stunnel.conf #sslVersion = TLSv1 pid = /var/run/stunnel.pid syslog = yes output = /var/log/stunnel.log debug = 3

[https] cert = /etc/stunnel/ssl/wildcard.blah.com.pem accept = 443 connect = 80 xforwardedfor = yes TIMEOUTbusy = 300 TIMEOUTclose = 0 TIMEOUTconnect = 10 TIMEOUTidle = 60

Is there anything we could add for performance tuning in stunnel? Any suggestions on what I could look for when this happens again would be appreciated. Our platform does between 2000 to 3000 rpm (request per minute) during peak hours.

We constantly see a lot of these messages every hour but I am not sure what is happening as the connections seem to be working.

SSL_accept: Peer suddenly disconnected

There was a higher spike of them as per the normal rate during our incident described above.

Thanks

Stephen Griffin Sr. System Administrator www.achievers.comhttp://www.achievers.com/

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