We have just released new stable Core-Admin release. See all details at:
Core-Admin 1.0.7673 ‘My name is human’ stable release is ready!
How to manage and configure URL redirects for your Web page using #WebhostingManagement and #CoreAdmin
Introduction to URL redirection with #CoreAdmin
In some cases you need to configure URL redirection so your web page can present different pages according to a source URL without having to do this configuration inside webpage.
You will need to have access to a working #WebhostingManagement installation where to configure URL redirections.
How to configure URL redirection with #CoreAdmin
URL redirection with #CoreAdmin is pretty straightforward. Click on the webhosting to manage and then go to URL redirect section as shown:
How URL redirection works with #CoreAdmin
All URL redirection configured is placed directly into Web server configuration, without touching your site .htaccess file (for example).
This makes possible to configure URL redirection not only for webpages with php but also for the rest of technologies available.
At the same time, this avoids any possibility to interfere with software doing .htaccess automatic changes like #Wordpress or #Prestashop.
URL redirection limits and performance
It is known working cases where users are configuring more than 40.000 url redirections without any issue. It is not known where could be performance problems though 40.000 is a good number.
Introduction to certificates generated with #WebhostingManagement
By default, all certificates created by the #WebhostingManagement uses .PEM format, which is suitable for most configurations.
In the case you want to export one of these certificates to .PFX format, follow next steps.
You need to have a working #WebhostingManagement installation with a certificate already installed (completed or flagged as ready).
You will need Administrator rights too (application admin, machine admin or platform admin).
Exporting a certificate to .PFX with Core-Admin
Get into the panel, click on the machine to manage or application (if you only have application admin rights) and click on the #WebhostingManagement application:
Then click to launch “export to .pfx” option:
Now select certificate to export. Only completed certificates (.CSR signed, sent to certificate authority, and got back response to complete certificate) and certificates flagged as ready will be showed for export.
After that, a window will appear with a link to download .pfx certicate. Click on it and your are done.
How to bounce a postfix message with Core-Admin
In the case you have a message in Postfix queue that you want to bounce without having to wait for queue max life time reached, you can use the following command provided by core-admin-tools package:
Install/update package core-admin-tools if you don’t have command crad-bounce.pyc. For that, use:
>> crad-update.pyc -u >> crad-update.pyc -g
Command line to bounce a message from Postfix Queue with Core-Admin
>> crad-bounce.pyc -b <postfixqueueid>
In such case, find message id to bounce using mailq as usual. For example:
>> mailq -Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient------- 6FC2068C00EF 7041 Wed Nov 29 19:11:08 soXXpeXX@josXXeasXXa.cXX XXlos.AmXXamXX@XXale.XX
With this information, you can bounce the message by running:
>> crad-bounce.pyc -b 6FC2068C00EF
- 1Introduction to Wordpress upgrade limit with Core-Admin
- 2About Wordpress automatic micro-updates
- 3About upgrading Wordpress, plugins and themes
- 4What updates are applied by Wordpress without user intervention
- 5Summary for all updates available for a Wordpress
- 6How to limit Wordpress updates using Core-Admin and #WordpressManager
Introduction to WordPress upgrade limit with Core-Admin
The following article explains what are the different wordpress upgrades available, what they cover, if they are automatic and which don’t. Those that are not automatic are considered manual and requires user intervention.
We also explain how you can disable these upgrades totally or partially using Core-Admin #WordpressManager.
About WordPress automatic micro-updates
Before considering disabling WordPress automatic updates, first keep on reading.
Automatic upgrades that can apply WordPress are always targeted to a very reduced and located inside WordPress engine. These upgrades are considered “minor” and only adds or fixes security features.
From WordPress webpage we have the following:
About upgrading WordPress, plugins and themes
Besides WordPress micro-updates (which only upgrades a very small and specific portion as we have said, never all WordPress engine), we have the following 3 categories that you can upgrade and apply to your WordPress:
- WordPress upgrades: these updates covers all WordPress engine (including micro-updates and going further).
- Plugin updates: these includes upgrades that are released by plugins developers. This is not considered WordPress code covered by previous section..
Having this classification in mind, we can visualize that in one hand we have micro-updates (which are safe) and in the other, we have general updates that might include version change and might potentially break your web (no smooth upgrade).
What updates are applied by WordPress without user intervention
As we have explained in previous sections, WordPress will never update automatically those parts that are not in WordPress’s control and that potentially might make your web stop working.
For that reason, WordPress only applies micro-updates.
For the same reason, WordPress never applies automatic updates without user intervention for WordPress engine, theme or plugins.
Those updates must be done and supervised by a specialized user, the site administrator/developer.
This way, the site developer/administrator can ensure that everything keeps working after upgrading and in such case, take actions if it stops working.
Summary for all updates available for a WordPress
Next it is shown a table that summarises all available updates, its features, etc:
the theme used by Wordpress
(no user intervention required)
|Yes||No, user must apply
|No, user must apply
|No, user must apply
|Can be disabled?||Yes||Yes, using Core-Admin Wordpress Manager||Yes, using Core-Admin Wordpress Manager||Yes, using Core-Admin Wordpress Manager|
|Is recommended to
disable these updates?
|No||Yes, if you think it is possible
these updaets might break
current project state
|Yes, if you think it is possible
these updaets might break
current project state
|Yes, if you think it is possible
these updaets might break
current project state
How to limit WordPress updates using Core-Admin and #WordpressManager
Use the following steps to limit part or all WordPress updates for a given installation.
- 1Introduction to Core-Admin tor integration
- 2How to enable Tor Network Integration with Core-Admin
- 3How to use this information about Tor Exit-Nodes with Core-Admin
- 4How to integrate Tor Network information provided by Core-Admin with MySQL
- 5How to block Tor Network with Core-Admin
- 6Command line options to manage Tor Network integration with Core-Admin
- 7Something missing or have a doubt? We want to hear your opinion!
Introduction to Core-Admin tor integration
Tor Network is an anonymizer network infrastructure, opened for everyone for use, that allows users to hide their location (mostly IP) or make it difficult to track (https://www.torproject.org/). As its function implies, it can be used to protect users from abuse and tracking.
However, you might be interested in have additional information about how Tor is used to access your services to implement analysis, apply policy or maybe blocking all traffic that might come from Tor (legitimate or not).
Due to the way Tor Network works, all exit nodes are public and can be downloaded. Combined with some tracking functions, it is possible to know if an IP belongs to Tor Network (as an exit node) or was part of it in the past.
Core-Admin provides an integration option that allows having all this information in an usable form so you can integrate it with your infrastructure:
How to enable Tor Network Integration with Core-Admin
For that, open #IpBlocker application as shown:
and then, click to configure:
After that, click to enable Tor Integration as shown:
After enabling it, you will have in your system, an up to database information about Tor Exit-Nodes that are active or were active in the past.
How to use this information about Tor Exit-Nodes with Core-Admin
By enabling this basic integration you have different indications out of the box that can be used. Some of then are the following.
Support to get an indication if a Tor node is detected when checking #IpBlocker tool. That way you will be able to get additional information when checking attacks:
Also, you will also get additional information when requesting for a report about certain ip:
How to integrate Tor Network information provided by Core-Admin with MySQL
To start doing more advanced things, you might be interested in having all this information in a MySQL table (two tables) so you can implement your own queries.
This way, you can not only check, you can also make your application to tag, do quick searches or implement resource policy control and protection.
For example, you might want to deny or allow login if source connection is inside or not Tor Network.
To enable Tor Network integration with MySQL, follow next steps as shown, and input the database were you what the information to be exported and updated. You can configure several MySQL databases.
Core-Admin will keep that MySQL information updated, leaving the rest of the tables untouched. This can be used for empty dedicated MySQL or existing MySQL databases, with working data where a couple of tables will appear and keep updated so your application can access this information using current MySQL API.
How to block Tor Network with Core-Admin
In the case you don’t want any of your services to be available/reachable to any Tor Exit-Node, then use the following option. It will create automatically IP firewall blocking for all exit nodes found. These rules will be updated regularly removing old exit nodes, and adding new active exit nodes.
Command line options to manage Tor Network integration with Core-Admin
There are different options available through crad-ip-blocker.pyc tool. Run the following command to get information about them:
>> crad-ip-blocker.pyc --help | grep tor also removes old blocking history (retaining last --update-tor-exit-nodes-list --find-all-tor-access --check-tor-ip=IP[,IP2[,IP3]] in tor (active,historic) network or not. --export-tor-tracking-to-mysql-db=DBNAME[,DBNAME2[,DBNAME3]] --dump-tor-tracking Allows to dump all tor tracking information current stored. --block-active-tor-nodes Allows to block all tor actives nodes currently found. /crad-ip-blocker.pyc --update-tor-exit-nodes-list to --unblock-active-tor-nodes active-tor-nodes. Use this option to remove all rules created by --block-active-tor-nodes options.
Something missing or have a doubt? We want to hear your opinion!
Please, if you have a question or a comment, contact us at firstname.lastname@example.org (https://www.core-admin.com/portal/about-us/contact).
Introduction to activate ssh access for a hosting with Core-Admin
By default, all hostings created with Core-Admin will have an individual user to ensure each hosting runs with isolated permissions.
This hosting user has no way to access through ssh, even it if opened ssh port and a password is configured.
This article, explain how to enable or disable ssh access for a given hosting using Core-Admin.
Be sure you have a firewall controlling SSH port (usually 22/tcp) to avoid leaving it open for everyone. It should be limited.
If you don’t have a firewall installed, use #Firewall manager. See the following manual to know how to configure it.
How to activate ssh access to a hosting for Core-Admin
Use the following steps. You will need Administrator rights to complete these steps.
First, open #WebHostingManagement application like this:
Then, open available option to manage SSH access:
After that, select the right hosting to configure and if you want to enable or disable SSH access like this:
Once the process is completed, the system will present you a set of configuration notes ready to use:
How to disable SSH access for particular hosting with Core-Admin
In the case you want to disable SSH access, just follow same steps as described before but selecting “disable” inside “Ssh access”.
How to list hostings with SSH access with Core-Admin
Use available option located at the top level tree:
Introduction to ipset with Core-Admin
In the case you want to block a large amount of IPs (more that 500 ips/networks), then you might notice that default block-by-iptables setting is not fast enough, and it tends to create a large iptables rule set with a bad performance.
If this is your case, here is how to configure your #IpBlocker tool to use linux kernel ipset.
Prerequisites for ipset with Core-Admin
This option is not available for Debian Lenny, Debian Squeeze and Centos 6 due to poor or missing ipset support.
How to enable it ipset with Core-Admin
#IpBlocker is prepared to switch to block-by-ipset from block-by-iptables and viceversa anytime you need it. This includes cases where the firewall is already enabled and working with a working set of blocking rules.
To enable it, just follow next steps. Open #IpBlocker tool as shown (it needs administrator permissions):
Then, open configuration:
Then, select block-by-ipset in block mode and then save. If it is not available, please, update your core-admin installation. Depending on the number of rules your machine has, it might take a few minutes to switch to ipset:
If everything went ok, you will use #IpBlocker as usual (and the rest of the system too). No additional step is required because once it is done, it is transparent to the user and system.
Some internal details on how is used ipset with Core-Admin
Under ipset mode, core-admin install only a few rules inside iptables and ip6tables chain to link ipsets created.
>> iptables -S | grep set -A INPUT -m set --match-set core_admin_blacklist_ipv4_net src -j DROP -A INPUT -m set --match-set core_admin_blacklist_ipv4 src -j DROP -A FORWARD -m set --match-set core_admin_blacklist_ipv4_net src -j DROP -A FORWARD -m set --match-set core_admin_blacklist_ipv4 src -j DROP -A OUTPUT -m set --match-set core_admin_blacklist_ipv4_net src -j DROP -A OUTPUT -m set --match-set core_admin_blacklist_ipv4 src -j DROP
These “sets” are accesible running common ipset commands (do not minipulate them directly, use #IpBlocker application or crad-ip-blocker.pyc command line tool):
>> ipset list
In order to integrate your login failures with crad-log-watcher, to have remote IP blocked automatically when some number of login failures are reached, follow the next guide.
Next steps will help you to create a login failure handler that will track and manage login failures for any given application, to block source IP in the case a configurable threshold is reached.
First, you have to make your web or server application to generate a log indication about the IP that is going to be blocked.
We recommend sending this log to syslog because it is accesible to all system users and requires no special privileges. That will simply next steps. If you decide to send this information to another log, just adapt everything as needed.
With PHP, generating such log will be:
// in case of login failure :: $remoteAddr = $_SERVER['REMOTE_ADDR']; $currentWeb = $_SERVER['SERVER_NAME']; $loginAttempted = // point this variable to the login that was attempted and failed syslog (LOG_INFO, "Login failure from [$remoteAddr] access denied to [$currentWeb] with user [$loginAttempted]");
This will make record a log to syslog everytime a login failure happens.
This change will be required for every web page or server to be protected.
Now, you have to create a custom handler for crad-log-watcher that reads these logs, keep track about login failures and block IPs reaching a threshold:
For that, create a file called login_failure_handler.py with the following content (adapt as needed):
#!/usr/bin/python from core_admin_common import support from core_admin_agent import checker, watcher # database for tracking login failures database_path = "/etc/core-admin/client/my.watcher.sql" def init (): # notify this is child for checker notification checker.is_child = True # track and lock login failures (status, info) = watcher.create_track_login_failure_tables (database_path) if not status: return (False, "Unable to create ip_registry table, error was: %s" % info) return (True, None) # return ok init def handle_line (line, source_log): # only process log failures to block if "login failure from [" in line.lower () and "access denied to [" in line.lower (): # assuming log error format: # Jul 7 16:15:29 node04-grupodw python: Login failure from [188.8.131.52] access denied to [http://foobar.com] with user [userAccess1] source_ip_to_block = line.lower ().split ("login failure from [").split ("]") login_failure_because = line.lower ().split ("access denied to [").split ("]") user_login = line.lower ().split ("with user [").split ("]") # configure notification reason = "Access failure to %s" % login_failure_because fail_logins_before_block = 10 # call to track user and ip watcher.track_and_report_login_failure (user_login, source_ip_to_block, reason, database_path, fail_logins_before_block, source_log) # end if return
Now, place these file into /var/beep/core-admin/client-agent/log-handlers
Now, inside /etc/core-admin/client/log-watcher.d, create a file that links your /var/log/syslog with the handler you have just created. For example, make that file have the following path: /etc/core-admin/client/log-watcher.d/custom-login-failures-blocker
<log src="/var/log/syslog" handler="login_failure_handler" />
- After that, just restart crad-log-watcher to have it loading your login_failure_handler and configuration created with:
- Supervise crad-log-watcher execution to ensure everything is working with:
# tail -f /var/log/syslog | grep crad-log-watcher
Now, test your development by causing login failures to protected system. You should see logs created at /var/log/syslog.
If you do not see login failure logs, it will not work. Review your code to ensure these logs are created.
If login failure logs are created, then run the following command just to show if login failure tracking is happening:
# sqlite3 -column -header /etc/core-admin/client/syslog.watcher.sql "select * from login_failure"
Have any questions? Contact us at email@example.com (https://www.core-admin.com/portal/about-us/contact).
- Dovecot broken indexes
- Panic: file mail-index-sync-keywords.c:
If you have problems while accessing to a mailbox and after reviewing logs you find something like:
Jul 4 10:44:22 claudia dovecot: imap(firstname.lastname@example.org): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:44:31 claudia dovecot: imap(email@example.com): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:45:04 claudia dovecot: imap(firstname.lastname@example.org): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:45:23 claudia dovecot: imap(email@example.com): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:45:34 claudia dovecot: imap(firstname.lastname@example.org): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:46:40 claudia dovecot: imap(email@example.com): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record)) Jul 4 10:48:45 claudia dovecot: imap(firstname.lastname@example.org): Panic: file mail-index-sync-keywords.c: line 227 (keywords_update_records): assertion failed: (data_offset >= sizeof(struct mail_index_record))
Then, one or more dovecot index and/or cache files are broken. This happens due to moving a mailbox from different dovecot versions. It can also happens with
outdated dovecot servers.
Core-Admin will detect these errors automatically and will report a: dovecot_mailbox_broken_indexes
Click on it and then click on “Reset dovecot indexes”.
That will clear all dovecot indexes at the destination machine, for the failing mailbox.
If you want to fix it manually, locate mailbox associated to the user and run the following command
(update it accordingly to the user mailbox failing):
>> find /var/spool/dovecot/mail/core-admin.com/someuser -name 'dovecot*' -type f -delete"
After that, you should have fixed the problem. No dovecot restart required.