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I'm building an active-passive cluster for an web application running on Apache.One of the the two servers will be avialable at a given time under a virtual IP (pacemaker is used as the cluster resource manager and corosync provides the communication layer). How would I configure both server to present a certificate for the virtual IP or better say for the FQDN that identifies the cluster ?

Thank you for any suggestions!

EDIT: I'm running CentOS 7

I've installed mod_ssl and the changes were made to the ssl.conffile:

[root@otrs2 pacemaker]# vi /etc/httpd/conf.d/ssl.conf
[root@otrs2 pacemaker]# clear
[root@otrs2 pacemaker]# less /etc/httpd/conf.d/ssl.conf
[root@otrs2 pacemaker]# more /etc/httpd/conf.d/ssl.conf
#
# When we also provide SSL we have to listen to the
# the HTTPS port in addition.
#
Listen 443 https

##
##  SSL Global Context
##
##  All SSL configuration in this context applies both to
##  the main server and all SSL-enabled virtual hosts.
##

#   Pass Phrase Dialog:
#   Configure the pass phrase gathering process.
#   The filtering dialog program (`builtin' is a internal
#   terminal dialog) has to provide the pass phrase on stdout.
SSLPassPhraseDialog exec:/usr/libexec/httpd-ssl-pass-dialog

#   Inter-Process Session Cache:
#   Configure the SSL Session Cache: First the mechanism
#   to use and second the expiring timeout (in seconds).
SSLSessionCache         shmcb:/run/httpd/sslcache(512000)
SSLSessionCacheTimeout  300

#   Pseudo Random Number Generator (PRNG):
#   Configure one or more sources to seed the PRNG of the
#   SSL library. The seed data should be of good random quality.
#   WARNING! On some platforms /dev/random blocks if not enough entropy
#   is available. This means you then cannot use the /dev/random device
#   because it would lead to very long connection times (as long as
#   it requires to make more entropy available). But usually those
#   platforms additionally provide a /dev/urandom device which doesn't
#   block. So, if available, use this one instead. Read the mod_ssl User
#   Manual for more details.
SSLRandomSeed startup file:/dev/urandom  256
SSLRandomSeed connect builtin
#SSLRandomSeed startup file:/dev/random  512
#SSLRandomSeed connect file:/dev/random  512
#SSLRandomSeed connect file:/dev/urandom 512

#
# Use "SSLCryptoDevice" to enable any supported hardware
# accelerators. Use "openssl engine -v" to list supported
# engine names.  NOTE: If you enable an accelerator and the
# server does not start, consult the error logs and ensure
# your accelerator is functioning properly.
#
SSLCryptoDevice builtin
#SSLCryptoDevice ubsec

##
## SSL Virtual Host Context
##

<VirtualHost _default_:443>

# General setup for the virtual host, inherited from global configuration
#DocumentRoot "/var/www/html"
#ServerName www.example.com:443

# Use separate log files for the SSL virtual host; note that LogLevel
# is not inherited from httpd.conf.
ErrorLog logs/ssl_error_log
TransferLog logs/ssl_access_log
LogLevel warn

#   SSL Engine Switch:
#   Enable/Disable SSL for this virtual host.
SSLEngine on

#   SSL Protocol support:
# List the enable protocol levels with which clients will be able to
# connect.  Disable SSLv2 access by default:
SSLProtocol all -SSLv2

#   SSL Cipher Suite:
#   List the ciphers that the client is permitted to negotiate.
#   See the mod_ssl documentation for a complete list.
SSLCipherSuite HIGH:MEDIUM:!aNULL:!MD5:!SEED:!IDEA

#   Speed-optimized SSL Cipher configuration:
#   If speed is your main concern (on busy HTTPS servers e.g.),
#   you might want to force clients to specific, performance
#   optimized ciphers. In this case, prepend those ciphers
#   to the SSLCipherSuite list, and enable SSLHonorCipherOrder.
#   Caveat: by giving precedence to RC4-SHA and AES128-SHA
#   (as in the example below), most connections will no longer
#   have perfect forward secrecy - if the server's key is
#   compromised, captures of past or future traffic must be
#   considered compromised, too.
#SSLCipherSuite RC4-SHA:AES128-SHA:HIGH:MEDIUM:!aNULL:!MD5
#SSLHonorCipherOrder on

#   Server Certificate:
# Point SSLCertificateFile at a PEM encoded certificate.  If
# the certificate is encrypted, then you will be prompted for a
# pass phrase.  Note that a kill -HUP will prompt again.  A new
# certificate can be generated using the genkey(1) command.
SSLCertificateFile /etc/pki/tls/certs/otrs2.crt

#   Server Private Key:
#   If the key is not combined with the certificate, use this
#   directive to point at the key file.  Keep in mind that if
#   you've both a RSA and a DSA private key you can configure
#   both in parallel (to also allow the use of DSA ciphers, etc.)
SSLCertificateKeyFile /etc/pki/tls/private/otrs2.key

#   Server Certificate Chain:
#   Point SSLCertificateChainFile at a file containing the
#   concatenation of PEM encoded CA certificates which form the
#   certificate chain for the server certificate. Alternatively
#   the referenced file can be the same as SSLCertificateFile
#   when the CA certificates are directly appended to the server
#   certificate for convinience.
#SSLCertificateChainFile /etc/pki/tls/certs/server-chain.crt

#   Certificate Authority (CA):
#   Set the CA certificate verification path where to find CA
#   certificates for client authentication or alternatively one
#   huge file containing all of them (file must be PEM encoded)
#SSLCACertificateFile /etc/pki/tls/certs/ca-bundle.crt

#   Client Authentication (Type):
#   Client certificate verification type and depth.  Types are
#   none, optional, require and optional_no_ca.  Depth is a
#   number which specifies how deeply to verify the certificate
#   issuer chain before deciding the certificate is not valid.
#SSLVerifyClient require
#SSLVerifyDepth  10

#   Access Control:
#   With SSLRequire you can do per-directory access control based
#   on arbitrary complex boolean expressions containing server
#   variable checks and other lookup directives.  The syntax is a
#   mixture between C and Perl.  See the mod_ssl documentation
#   for more details.
#<Location />
#SSLRequire (    %{SSL_CIPHER} !~ m/^(EXP|NULL)/ \
#            and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \
#            and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"} \
#            and %{TIME_WDAY} >= 1 and %{TIME_WDAY} <= 5 \
#            and %{TIME_HOUR} >= 8 and %{TIME_HOUR} <= 20       ) \
#           or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/
#</Location>

#   SSL Engine Options:
#   Set various options for the SSL engine.
#   o FakeBasicAuth:
#     Translate the client X.509 into a Basic Authorisation.  This means that
#     the standard Auth/DBMAuth methods can be used for access control.  The
#     user name is the `one line' version of the client's X.509 certificate.
#     Note that no password is obtained from the user. Every entry in the user
#     file needs this password: `xxj31ZMTZzkVA'.
#   o ExportCertData:
#     This exports two additional environment variables: SSL_CLIENT_CERT and
#     SSL_SERVER_CERT. These contain the PEM-encoded certificates of the
#     server (always existing) and the client (only existing when client
#     authentication is used). This can be used to import the certificates
#     into CGI scripts.
#   o StdEnvVars:
#     This exports the standard SSL/TLS related `SSL_*' environment variables.
#     Per default this exportation is switched off for performance reasons,
#     because the extraction step is an expensive operation and is usually
#     useless for serving static content. So one usually enables the
#     exportation for CGI and SSI requests only.
#   o StrictRequire:
#     This denies access when "SSLRequireSSL" or "SSLRequire" applied even
#     under a "Satisfy any" situation, i.e. when it applies access is denied
#     and no other module can change it.
#   o OptRenegotiate:
#     This enables optimized SSL connection renegotiation handling when SSL
#     directives are used in per-directory context.
#SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire
<Files ~ "\.(cgi|shtml|phtml|php3?)$">
    SSLOptions +StdEnvVars
</Files>
<Directory "/var/www/cgi-bin">
    SSLOptions +StdEnvVars
</Directory>

#   SSL Protocol Adjustments:
#   The safe and default but still SSL/TLS standard compliant shutdown
#   approach is that mod_ssl sends the close notify alert but doesn't wait for
#   the close notify alert from client. When you need a different shutdown
#   approach you can use one of the following variables:
#   o ssl-unclean-shutdown:
#     This forces an unclean shutdown when the connection is closed, i.e. no
#     SSL close notify alert is send or allowed to received.  This violates
#     the SSL/TLS standard but is needed for some brain-dead browsers. Use
#     this when you receive I/O errors because of the standard approach where
#     mod_ssl sends the close notify alert.
#   o ssl-accurate-shutdown:
#     This forces an accurate shutdown when the connection is closed, i.e. a
#     SSL close notify alert is send and mod_ssl waits for the close notify
#     alert of the client. This is 100% SSL/TLS standard compliant, but in
#     practice often causes hanging connections with brain-dead browsers. Use
#     this only for browsers where you know that their SSL implementation
#     works correctly.
#   Notice: Most problems of broken clients are also related to the HTTP
#   keep-alive facility, so you usually additionally want to disable
#   keep-alive for those clients, too. Use variable "nokeepalive" for this.
#   Similarly, one has to force some clients to use HTTP/1.0 to workaround
#   their broken HTTP/1.1 implementation. Use variables "downgrade-1.0" and
#   "force-response-1.0" for this.
BrowserMatch "MSIE [2-5]" \
         nokeepalive ssl-unclean-shutdown \
         downgrade-1.0 force-response-1.0

#   Per-Server Logging:
#   The home of a custom SSL log file. Use this when you want a
#   compact non-error SSL logfile on a virtual host basis.
CustomLog logs/ssl_request_log \
          "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"

</VirtualHost>

2 VH's :

<VirtualHost *:443>
    DocumentRoot "/www/example1"
    ServerName otrs1
    #place here the directive to point to the cert for otrs1
    # Other directives here
</VirtualHost>

<VirtualHost *:443>
    DocumentRoot "/www/example2"
    ServerName otrs-vip
     #place here the directive to point to the cert for otrs-vip
    # Other directives here
</VirtualHost>
postFix
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1 Answers1

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Add at the beginning NameVirtualHost *:443

Then use <virtualHost *:443> to listen on a specified port on all interfaces instead of default <virtualHost _default_:443> (there is a difference). When the servers doesn't hold VIP, it will respond on physical_ip:443 (on non-pacemaker ip) which is useful for healthcheck.

Once a server receives a VIP, no restart is necessary to start responding on VIP:443

Inside that VirtualHost use normal certificate directives.

kubanczyk
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  • What I proposed would work much better with pacemaker. Try your propostion and mine, compare. A misunderstanding may be that you seem to think that VIP is related to certificate. It's not. Usually certificate is only related to the HTTP Host header (as sent by a browser), so the certificate can be presented without a problem on VIP or nonVIP. – kubanczyk Mar 14 '18 at 15:11
  • So you are talking about this example ` with ServerName foo.com means "on all IPs managed on this host", "on port 80", "if the request host header is foo.com" I'll use this virtualhost` But wouldn't I then mix named and IP based Virtual Hosts? Is it best practice? Also, could I simply copy all the lines from my `ssl.conf` starting from `` to `` and adjust the certificate path etc. Something like in EDIT2 of my question ? Would that be the way to do it ? – postFix Mar 14 '18 at 19:39
  • @postFix You also need to `NameBasedVirtualHost *:80` then you have `if the request host header is foo.com" I'll use this virtualhost`. IP-based VirtualHost is an obsolete idea, it was needed in HTTP/1.0 times. And IP-based works awfully with VIP (pacemaker). – kubanczyk Mar 15 '18 at 08:37
  • ok I think I understand you. So basically I would have to have two VH's like this please see the 2 VH's section in my question. Is that correct? – postFix Mar 15 '18 at 08:43
  • @postFix Yes, but with `NameBasedVirtualHost *:443`. The `otrs1` seem an optional thing, but yes it will work. – kubanczyk Mar 15 '18 at 11:47
  • @kubacznyk I have added without the line `NameBasedVirtualHost *:443` and it worked. I have read somhwere that with Apache 2.4 the line is no longer needed. I've added the Virtual Host's to the `ssl.conf`` file. Yes the Virtual Host part for `otrs1` is optional but I'd like to have in case the clsuter and thus the VIP will be not available. Then I could still access each node via it's IP and otherwise it would present each time the certificate for the VIP FQDN and this would cause certificate errors in the browser. Am I correct? – postFix Mar 15 '18 at 11:58
  • `Prior to 2.3.11, NameVirtualHost was required to instruct the server that a particular IP address and port combination was usable as a name-based virtual host. In 2.3.11 and later, any time an IP address and port combination is used in multiple virtual hosts, name-based virtual hosting is automatically enabled for that address.` [Apache documentation](http://httpd.apache.org/docs/2.4/mod/core.html#namevirtualhost) – postFix Mar 17 '18 at 20:24