diff --git a/management/daemon.py b/management/daemon.py
index 15db5e0b..9b71b611 100755
--- a/management/daemon.py
+++ b/management/daemon.py
@@ -318,9 +318,9 @@ def dns_get_dump():
 @app.route('/ssl/csr/<domain>', methods=['POST'])
 @authorized_personnel_only
 def ssl_get_csr(domain):
-	from web_update import get_domain_ssl_files, create_csr
-	ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env)
-	return create_csr(domain, ssl_key, env)
+	from web_update import create_csr
+	ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
+	return create_csr(domain, ssl_private_key, env)
 
 @app.route('/ssl/install', methods=['POST'])
 @authorized_personnel_only
diff --git a/management/status_checks.py b/management/status_checks.py
index f92a4c3e..5bd8914d 100755
--- a/management/status_checks.py
+++ b/management/status_checks.py
@@ -13,7 +13,7 @@ import dateutil.parser, dateutil.tz
 import idna
 
 from dns_update import get_dns_zones, build_tlsa_record, get_custom_dns_config, get_secondary_dns
-from web_update import get_web_domains, get_default_www_redirects, get_domain_ssl_files, get_domains_with_a_records
+from web_update import get_web_domains, get_default_www_redirects, get_ssl_certificates, get_domain_ssl_files, get_domains_with_a_records
 from mailconfig import get_mail_domains, get_mail_aliases
 
 from utils import shell, sort_domains, load_env_vars_from_file, load_settings
@@ -248,19 +248,21 @@ def run_domain_checks(rounded_time, env, output, pool):
 	# Get the list of domains that we don't serve web for because of a custom CNAME/A record.
 	domains_with_a_records = get_domains_with_a_records(env)
 
+	ssl_certificates = get_ssl_certificates(env)
+
 	# Serial version:
 	#for domain in sort_domains(domains_to_check, env):
 	#	run_domain_checks_on_domain(domain, rounded_time, env, dns_domains, dns_zonefiles, mail_domains, web_domains)
 
 	# Parallelize the checks across a worker pool.
-	args = ((domain, rounded_time, env, dns_domains, dns_zonefiles, mail_domains, web_domains, domains_with_a_records)
+	args = ((domain, rounded_time, env, dns_domains, dns_zonefiles, mail_domains, web_domains, domains_with_a_records, ssl_certificates)
 		for domain in domains_to_check)
 	ret = pool.starmap(run_domain_checks_on_domain, args, chunksize=1)
 	ret = dict(ret) # (domain, output) => { domain: output }
 	for domain in sort_domains(ret, env):
 		ret[domain].playback(output)
 
-def run_domain_checks_on_domain(domain, rounded_time, env, dns_domains, dns_zonefiles, mail_domains, web_domains, domains_with_a_records):
+def run_domain_checks_on_domain(domain, rounded_time, env, dns_domains, dns_zonefiles, mail_domains, web_domains, domains_with_a_records, ssl_certificates):
 	output = BufferedOutput()
 
 	# The domain is IDNA-encoded in the database, but for display use Unicode.
@@ -282,7 +284,7 @@ def run_domain_checks_on_domain(domain, rounded_time, env, dns_domains, dns_zone
 		check_mail_domain(domain, env, output)
 
 	if domain in web_domains:
-		check_web_domain(domain, rounded_time, env, output)
+		check_web_domain(domain, rounded_time, ssl_certificates, env, output)
 
 	if domain in dns_domains:
 		check_dns_zone_suggestions(domain, env, output, dns_zonefiles, domains_with_a_records)
@@ -528,7 +530,7 @@ def check_mail_domain(domain, env, output):
 			which may prevent recipients from receiving your mail.
 			See http://www.spamhaus.org/dbl/ and http://www.spamhaus.org/query/domain/%s.""" % (dbl, domain))
 
-def check_web_domain(domain, rounded_time, env, output):
+def check_web_domain(domain, rounded_time, ssl_certificates, env, output):
 	# See if the domain's A record resolves to our PUBLIC_IP. This is already checked
 	# for PRIMARY_HOSTNAME, for which it is required for mail specifically. For it and
 	# other domains, it is required to access its website.
@@ -544,7 +546,7 @@ def check_web_domain(domain, rounded_time, env, output):
 	# We need a SSL certificate for PRIMARY_HOSTNAME because that's where the
 	# user will log in with IMAP or webmail. Any other domain we serve a
 	# website for also needs a signed certificate.
-	check_ssl_cert(domain, rounded_time, env, output)
+	check_ssl_cert(domain, rounded_time, ssl_certificates, env, output)
 
 def query_dns(qname, rtype, nxdomain='[Not Set]'):
 	# Make the qname absolute by appending a period. Without this, dns.resolver.query
@@ -571,19 +573,24 @@ def query_dns(qname, rtype, nxdomain='[Not Set]'):
 	# can compare to a well known order.
 	return "; ".join(sorted(str(r).rstrip('.') for r in response))
 
-def check_ssl_cert(domain, rounded_time, env, output):
+def check_ssl_cert(domain, rounded_time, ssl_certificates, env, output):
 	# Check that SSL certificate is signed.
 
 	# Skip the check if the A record is not pointed here.
 	if query_dns(domain, "A", None) not in (env['PUBLIC_IP'], None): return
 
 	# Where is the SSL stored?
-	ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env)
+	x = get_domain_ssl_files(domain, ssl_certificates, env, allow_missing_cert=True)
 
-	if not os.path.exists(ssl_certificate):
-		output.print_error("The SSL certificate file for this domain is missing.")
+	if x is None:
+		output.print_warning("""No SSL certificate is installed for this domain. Visitors to a website on
+			this domain will get a security warning. If you are not serving a website on this domain, you do
+			not need to take any action. Use the SSL Certificates page in the control panel to install a
+			SSL certificate.""")
 		return
 
+	ssl_key, ssl_certificate, ssl_via = x
+
 	# Check that the certificate is good.
 
 	cert_status, cert_status_details = check_certificate(domain, ssl_certificate, ssl_key, rounded_time=rounded_time)
@@ -607,16 +614,13 @@ def check_ssl_cert(domain, rounded_time, env, output):
 		if domain == env['PRIMARY_HOSTNAME']:
 			output.print_error("""The SSL certificate for this domain is currently self-signed. You will get a security
 			warning when you check or send email and when visiting this domain in a web browser (for webmail or
-			static site hosting). Use the SSL Certificates page in this control panel to install a signed SSL certificate.
+			static site hosting). Use the SSL Certificates page in the control panel to install a signed SSL certificate.
 			You may choose to leave the self-signed certificate in place and confirm the security exception, but check that
 			the certificate fingerprint matches the following:""")
 			output.print_line("")
 			output.print_line("   " + fingerprint, monospace=True)
 		else:
-			output.print_warning("""The SSL certificate for this domain is currently self-signed. Visitors to a website on
-			this domain will get a security warning. If you are not serving a website on this domain, then it is
-			safe to leave the self-signed certificate in place. Use the SSL Certificates page in this control panel to
-			install a signed SSL certificate.""")
+			output.print_error("""The SSL certificate for this domain is self-signed.""")
 
 	else:
 		output.print_error("The SSL certificate has a problem: " + cert_status)
@@ -630,8 +634,7 @@ def check_certificate(domain, ssl_certificate, ssl_private_key, warn_if_expiring
 	# for the provided domain.
 
 	from cryptography.hazmat.primitives.asymmetric.rsa import RSAPrivateKey
-	from cryptography.x509 import Certificate, DNSName, ExtensionNotFound, OID_COMMON_NAME, OID_SUBJECT_ALTERNATIVE_NAME
-	import idna
+	from cryptography.x509 import Certificate
 
 	# The ssl_certificate file may contain a chain of certificates. We'll
 	# need to split that up before we can pass anything to openssl or
@@ -646,33 +649,7 @@ def check_certificate(domain, ssl_certificate, ssl_private_key, warn_if_expiring
 	# First check that the domain name is one of the names allowed by
 	# the certificate.
 	if domain is not None:
-		# The domain may be found in the Subject Common Name (CN). This comes back as an IDNA (ASCII)
-		# string, which is the format we store domains in - so good.
-		certificate_names = set()
-		try:
-			certificate_names.add(
-				cert.subject.get_attributes_for_oid(OID_COMMON_NAME)[0].value
-				)
-		except IndexError:
-			# No common name? Certificate is probably generated incorrectly.
-			# But we'll let it error-out when it doesn't find the domain.
-			pass
-
-		# ... or be one of the Subject Alternative Names. The cryptography library handily IDNA-decodes
-		# the names for us. We must encode back to ASCII, but wildcard certificates can't pass through
-		# IDNA encoding/decoding so we must special-case. See https://github.com/pyca/cryptography/pull/2071.
-		def idna_decode_dns_name(dns_name):
-			if dns_name.startswith("*."):
-				return "*." + idna.encode(dns_name[2:]).decode('ascii')
-			else:
-				return idna.encode(dns_name).decode('ascii')
-
-		try:
-			sans = cert.extensions.get_extension_for_oid(OID_SUBJECT_ALTERNATIVE_NAME).value.get_values_for_type(DNSName)
-			for san in sans:
-				certificate_names.add(idna_decode_dns_name(san))
-		except ExtensionNotFound:
-			pass
+		certificate_names, cert_primary_name = get_certificate_domains(cert)
 
 		# Check that the domain appears among the acceptable names, or a wildcard
 		# form of the domain name (which is a stricter check than the specs but
@@ -792,6 +769,41 @@ def load_pem(pem):
 		return load_pem_x509_certificate(pem, default_backend())
 	raise ValueError("Unsupported PEM object type: " + pem_type.decode("ascii", "replace"))
 
+def get_certificate_domains(cert):
+	from cryptography.x509 import DNSName, ExtensionNotFound, OID_COMMON_NAME, OID_SUBJECT_ALTERNATIVE_NAME
+	import idna
+
+	names = set()
+	cn = None
+
+	# The domain may be found in the Subject Common Name (CN). This comes back as an IDNA (ASCII)
+	# string, which is the format we store domains in - so good.
+	try:
+		cn = cert.subject.get_attributes_for_oid(OID_COMMON_NAME)[0].value
+		names.add(cn)
+	except IndexError:
+		# No common name? Certificate is probably generated incorrectly.
+		# But we'll let it error-out when it doesn't find the domain.
+		pass
+
+	# ... or be one of the Subject Alternative Names. The cryptography library handily IDNA-decodes
+	# the names for us. We must encode back to ASCII, but wildcard certificates can't pass through
+	# IDNA encoding/decoding so we must special-case. See https://github.com/pyca/cryptography/pull/2071.
+	def idna_decode_dns_name(dns_name):
+		if dns_name.startswith("*."):
+			return "*." + idna.encode(dns_name[2:]).decode('ascii')
+		else:
+			return idna.encode(dns_name).decode('ascii')
+
+	try:
+		sans = cert.extensions.get_extension_for_oid(OID_SUBJECT_ALTERNATIVE_NAME).value.get_values_for_type(DNSName)
+		for san in sans:
+			names.add(idna_decode_dns_name(san))
+	except ExtensionNotFound:
+		pass
+
+	return names, cn
+
 _apt_updates = None
 def list_apt_updates(apt_update=True):
 	# See if we have this information cached recently.
@@ -1027,7 +1039,8 @@ if __name__ == "__main__":
 		domain = env['PRIMARY_HOSTNAME']
 		if query_dns(domain, "A") != env['PUBLIC_IP']:
 			sys.exit(1)
-		ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env)
+		ssl_certificates = get_ssl_certificates(env)
+		ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, ssl_certificates, env)
 		if not os.path.exists(ssl_certificate):
 			sys.exit(1)
 		cert_status, cert_status_details = check_certificate(domain, ssl_certificate, ssl_key, warn_if_expiring_soon=False)
diff --git a/management/templates/ssl.html b/management/templates/ssl.html
index c60c22f6..78837347 100644
--- a/management/templates/ssl.html
+++ b/management/templates/ssl.html
@@ -18,7 +18,7 @@
   </tbody>
 </table>
 
-<p>Advanced:<br>Install a multi-domain or wildcard certificate for the <code>{{hostname}}</code> domain to have it automatically applied to any domains it is valid for.</p>
+<p>A multi-domain or wildcard certificate will be automatically applied to any domains it is valid for.</p>
 
 <h3 id="ssl_install_header">Install SSL Certificate</h3>
 
diff --git a/management/web_update.py b/management/web_update.py
index d6f6c802..c9c93f60 100644
--- a/management/web_update.py
+++ b/management/web_update.py
@@ -60,6 +60,9 @@ def get_default_www_redirects(env):
 	return sort_domains(www_domains - web_domains - get_domains_with_a_records(env), env)
 
 def do_web_update(env):
+	# Pre-load what SSL certificates we will use for each domain.
+	ssl_certificates = get_ssl_certificates(env)
+
 	# Build an nginx configuration file.
 	nginx_conf = open(os.path.join(os.path.dirname(__file__), "../conf/nginx-top.conf")).read()
 
@@ -70,20 +73,20 @@ def do_web_update(env):
 	template3 = "\trewrite ^(.*) https://$REDIRECT_DOMAIN$1 permanent;\n"
 
 	# Add the PRIMARY_HOST configuration first so it becomes nginx's default server.
-	nginx_conf += make_domain_config(env['PRIMARY_HOSTNAME'], [template0, template1, template2], env)
+	nginx_conf += make_domain_config(env['PRIMARY_HOSTNAME'], [template0, template1, template2], ssl_certificates, env)
 
 	# Add configuration all other web domains.
 	has_root_proxy_or_redirect = get_web_domains_with_root_overrides(env)
 	for domain in get_web_domains(env):
 		if domain == env['PRIMARY_HOSTNAME']: continue # handled above
 		if domain not in has_root_proxy_or_redirect:
-			nginx_conf += make_domain_config(domain, [template0, template1], env)
+			nginx_conf += make_domain_config(domain, [template0, template1], ssl_certificates, env)
 		else:
-			nginx_conf += make_domain_config(domain, [template0], env)
+			nginx_conf += make_domain_config(domain, [template0], ssl_certificates, env)
 
 	# Add default www redirects.
 	for domain in get_default_www_redirects(env):
-		nginx_conf += make_domain_config(domain, [template0, template3], env)
+		nginx_conf += make_domain_config(domain, [template0, template3], ssl_certificates, env)
 
 	# Did the file change? If not, don't bother writing & restarting nginx.
 	nginx_conf_fn = "/etc/nginx/conf.d/local.conf"
@@ -104,18 +107,14 @@ def do_web_update(env):
 
 	return "web updated\n"
 
-def make_domain_config(domain, templates, env):
+def make_domain_config(domain, templates, ssl_certificates, env):
 	# GET SOME VARIABLES
 
 	# Where will its root directory be for static files?
 	root = get_web_root(domain, env)
 
 	# What private key and SSL certificate will we use for this domain?
-	ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env)
-
-	# For hostnames created after the initial setup, ensure we have an SSL certificate
-	# available. Make a self-signed one now if one doesn't exist.
-	ensure_ssl_certificate_exists(domain, ssl_key, ssl_certificate, env)
+	ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, ssl_certificates, env)
 
 	# ADDITIONAL DIRECTIVES.
 
@@ -186,77 +185,140 @@ def get_web_root(domain, env, test_exists=True):
 		if os.path.exists(root) or not test_exists: break
 	return root
 
-def get_domain_ssl_files(domain, env, allow_shared_cert=True):
-	# What SSL private key will we use? Allow the user to override this, but
-	# in many cases using the same private key for all domains would be fine.
-	# Don't allow the user to override the key for PRIMARY_HOSTNAME because
-	# that's what's in the main file.
-	ssl_key = os.path.join(env["STORAGE_ROOT"], 'ssl/ssl_private_key.pem')
-	ssl_key_is_alt = False
-	alt_key = os.path.join(env["STORAGE_ROOT"], 'ssl/%s/private_key.pem' % safe_domain_name(domain))
-	if domain != env['PRIMARY_HOSTNAME'] and os.path.exists(alt_key):
-		ssl_key = alt_key
-		ssl_key_is_alt = True
+def get_ssl_certificates(env):
+	# Scan all of the installed SSL certificates and map every domain
+	# that the certificates are good for to the best certificate for
+	# the domain.
+
+	from cryptography.hazmat.primitives.asymmetric.rsa import RSAPrivateKey
+	from cryptography.x509 import Certificate
+
+	# The certificates are all stored here:
+	ssl_root = os.path.join(env["STORAGE_ROOT"], 'ssl')
+
+	# List all of the files in the SSL directory and one level deep.
+	def get_file_list():
+		for fn in os.listdir(ssl_root):
+			fn = os.path.join(ssl_root, fn)
+			if os.path.isfile(fn):
+				yield fn
+			elif os.path.isdir(fn):
+				for fn1 in os.listdir(fn):
+					fn1 = os.path.join(fn, fn1)
+					if os.path.isfile(fn1):
+						yield fn1
+
+	# Remember stuff.
+	private_keys = { }
+	certificates = [ ]
+
+	# Scan each of the files to find private keys and certificates.
+	# We must load all of the private keys first before processing
+	# certificates so that we can check that we have a private key
+	# available before using a certificate.
+	from status_checks import load_cert_chain, load_pem
+	for fn in get_file_list():
+		try:
+			pem = load_pem(load_cert_chain(fn)[0])
+		except ValueError:
+			# Not a valid PEM format for a PEM type we care about.
+			continue
+
+		# Remember where we got this object.
+		pem._filename = fn
+
+		# Is it a private key?
+		if isinstance(pem, RSAPrivateKey):
+			private_keys[pem.public_key().public_numbers()] = pem
+
+		# Is it a certificate?
+		if isinstance(pem, Certificate):
+			certificates.append(pem)
+
+	# Process the certificates.
+	domains = { }
+	from status_checks import get_certificate_domains
+	for cert in certificates:
+		# What domains is this certificate good for?
+		cert_domains, primary_domain = get_certificate_domains(cert)
+		cert._primary_domain = primary_domain
+
+		# Is there a private key file for this certificate?
+		private_key = private_keys.get(cert.public_key().public_numbers())
+		if not private_key:
+			continue
+		cert._private_key = private_key
+
+		# Add this cert to the list of certs usable for the domains.
+		for domain in cert_domains:
+			domains.setdefault(domain, []).append(cert)
+
+	# Sort the certificates to prefer good ones.
+	import datetime
+	now = datetime.datetime.utcnow()
+	ret = { }
+	for domain, cert_list in domains.items():
+		cert_list.sort(key = lambda cert : (
+			# must be valid NOW
+			cert.not_valid_before <= now <= cert.not_valid_after,
+
+			# prefer one that is not self-signed
+			cert.issuer != cert.subject,
+
+			# prefer one with the expiration furthest into the future so
+			# that we can easily rotate to new certs as we get them
+			cert.not_valid_after,
+
+			# in case a certificate is installed in multiple paths,
+			# prefer the... lexicographically last one?
+			cert._filename,
+
+		), reverse=True)
+		cert = cert_list.pop(0)
+		ret[domain] = {
+			"private-key": cert._private_key._filename,
+			"certificate": cert._filename,
+			"primary-domain": cert._primary_domain,
+			}
+
+	return ret
+
+def get_domain_ssl_files(domain, ssl_certificates, env, allow_missing_cert=False):
+	# Get the default paths.
+	ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
+	ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_certificate.pem'))
 
-	# What SSL certificate will we use?
-	ssl_certificate_primary = os.path.join(env["STORAGE_ROOT"], 'ssl/ssl_certificate.pem')
-	ssl_via = None
 	if domain == env['PRIMARY_HOSTNAME']:
-		# For PRIMARY_HOSTNAME, use the one we generated at set-up time.
-		ssl_certificate = ssl_certificate_primary
+		# The primary domain must use the server certificate because
+		# it is hard-coded in some service configuration files.
+		return ssl_private_key, ssl_certificate, None
+
+	wildcard_domain = re.sub("^[^\.]+", "*", domain)
+
+	if domain in ssl_certificates:
+		cert_info = ssl_certificates[domain]
+		cert_type = "multi-domain"
+	elif wildcard_domain in ssl_certificates:
+		cert_info = ssl_certificates[wildcard_domain]
+		cert_type = "wildcard"
+	elif not allow_missing_cert:
+		# No certificate is available for this domain! Return default files.
+		ssl_via = "Using certificate for %s." % env['PRIMARY_HOSTNAME']
+		return ssl_private_key, ssl_certificate, ssl_via
 	else:
-		# For other domains, we'll probably use a certificate in a different path.
-		ssl_certificate = os.path.join(env["STORAGE_ROOT"], 'ssl/%s/ssl_certificate.pem' % safe_domain_name(domain))
+		# No certificate is available - and warn appropriately.
+		return None
 
-		# But we can be smart and reuse the main SSL certificate if is has
-		# a Subject Alternative Name matching this domain. Don't do this if
-		# the user has uploaded a different private key for this domain.
-		if not ssl_key_is_alt and allow_shared_cert:
-			from status_checks import check_certificate
-			if check_certificate(domain, ssl_certificate_primary, None, just_check_domain=True)[0] == "OK":
-				ssl_certificate = ssl_certificate_primary
-				ssl_via = "Using multi/wildcard certificate of %s." % env['PRIMARY_HOSTNAME']
+	# 'via' is a hint to the user about which certificate is in use for the domain
+	if cert_info['certificate'] == os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_certificate.pem'):
+		# Using the server certificate.
+		via = "Using same %s certificate as for %s." % (cert_type, env['PRIMARY_HOSTNAME'])
+	elif cert_info['primary-domain'] != domain and cert_info['primary-domain'] in ssl_certificates and cert_info == ssl_certificates[cert_info['primary-domain']]:
+		via = "Using same %s certificate as for %s." % (cert_type, cert_info['primary-domain'])
+	else:
+		via = None # don't show a hint - show expiration info instead
 
-			# For a 'www.' domain, see if we can reuse the cert of the parent.
-			elif domain.startswith('www.'):
-				ssl_certificate_parent = os.path.join(env["STORAGE_ROOT"], 'ssl/%s/ssl_certificate.pem' % safe_domain_name(domain[4:]))
-				if os.path.exists(ssl_certificate_parent) and check_certificate(domain, ssl_certificate_parent, None, just_check_domain=True)[0] == "OK":
-					ssl_certificate = ssl_certificate_parent
-					ssl_via = "Using multi/wildcard certificate of %s." % domain[4:]
-
-	return ssl_key, ssl_certificate, ssl_via
-
-def ensure_ssl_certificate_exists(domain, ssl_key, ssl_certificate, env):
-	# For domains besides PRIMARY_HOSTNAME, generate a self-signed certificate if
-	# a certificate doesn't already exist. See setup/mail.sh for documentation.
-
-	if domain == env['PRIMARY_HOSTNAME']:
-		return
-
-	# Sanity check. Shouldn't happen. A non-primary domain might use this
-	# certificate (see above), but then the certificate should exist anyway.
-	if ssl_certificate == os.path.join(env["STORAGE_ROOT"], 'ssl/ssl_certificate.pem'):
-		return
-
-	if os.path.exists(ssl_certificate):
-		return
-
-	os.makedirs(os.path.dirname(ssl_certificate), exist_ok=True)
-
-	# Generate a new self-signed certificate using the same private key that we already have.
-
-	# Start with a CSR written to a temporary file.
-	with tempfile.NamedTemporaryFile(mode="w") as csr_fp:
-		csr_fp.write(create_csr(domain, ssl_key, env))
-		csr_fp.flush() # since we won't close until after running 'openssl x509', since close triggers delete.
-
-		# And then make the certificate.
-		shell("check_call", [
-			"openssl", "x509", "-req",
-			"-days", "365",
-			"-in", csr_fp.name,
-			"-signkey", ssl_key,
-			"-out", ssl_certificate])
+	return cert_info['private-key'], cert_info['certificate'], via
 
 def create_csr(domain, ssl_key, env):
 	return shell("check_output", [
@@ -278,8 +340,8 @@ def install_cert(domain, ssl_cert, ssl_chain, env):
 
 	# Do validation on the certificate before installing it.
 	from status_checks import check_certificate
-	ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env, allow_shared_cert=False)
-	cert_status, cert_status_details = check_certificate(domain, fn, ssl_key)
+	ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
+	cert_status, cert_status_details = check_certificate(domain, fn, ssl_private_key)
 	if cert_status != "OK":
 		if cert_status == "SELF-SIGNED":
 			cert_status = "This is a self-signed certificate. I can't install that."
@@ -288,7 +350,24 @@ def install_cert(domain, ssl_cert, ssl_chain, env):
 			cert_status += " " + cert_status_details
 		return cert_status
 
-	# Copy the certificate to its expected location.
+	# Where to put it?
+	if domain == env['PRIMARY_HOSTNAME']:
+		ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_certificate.pem'))
+	else:
+		# Make a unique path for the certificate.
+		from status_checks import load_cert_chain, load_pem, get_certificate_domains
+		from cryptography.hazmat.primitives import hashes
+		from binascii import hexlify
+		cert = load_pem(load_cert_chain(fn)[0])
+		all_domains, cn = get_certificate_domains(cert)
+		path = "%s-%s-%s" % (
+			cn, # common name
+			cert.not_valid_after.date().isoformat().replace("-", ""), # expiration date
+			hexlify(cert.fingerprint(hashes.SHA256())).decode("ascii")[0:8], # fingerprint prefix
+			)
+		ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', path, 'ssl_certificate.pem'))
+
+	# Install the certificate.
 	os.makedirs(os.path.dirname(ssl_certificate), exist_ok=True)
 	shutil.move(fn, ssl_certificate)
 
@@ -314,9 +393,10 @@ def get_web_domains_info(env):
 	# for the SSL config panel, get cert status
 	def check_cert(domain):
 		from status_checks import check_certificate
-		ssl_key, ssl_certificate, ssl_via = get_domain_ssl_files(domain, env)
-		if not os.path.exists(ssl_certificate):
-			return ("danger", "No Certificate Installed")
+		ssl_certificates = get_ssl_certificates(env)
+		x = get_domain_ssl_files(domain, ssl_certificates, env, allow_missing_cert=True)
+		if x is None: return ("danger", "No Certificate Installed")
+		ssl_key, ssl_certificate, ssl_via = x
 		cert_status, cert_status_details = check_certificate(domain, ssl_certificate, ssl_key)
 		if cert_status == "OK":
 			if not ssl_via: