KernelCare Enterprise (ePortal)

KernelCare Enterprise includes a web management console (ePortal) for protected environments.

ePortal software can help protect servers located behind the firewall (i.e. with no internet access) and can be installed both on-premises and in the cloud.

ePortal Hardware Requirements

ePortal machine disk size doesn't change with the number of connected servers.

Requirements are always the same:

  • 100 GB minimum
  • 200 GB recommended
  • SSD


SSD based storage is a crucial requirement for ePortal server.

As far as other requirements concerned, we have tested the following configuration and the following number of connected servers:

  • 10k of connected machines is the maximum for the following requirements:
    • VM
    • 1 VCPU
    • 1 GB RAM
  • 75k of connected machines is the maximum for the following requirements:
    • Core i5
    • 1 CPU
    • 4 GB RAM


KernelCare.ePortal is compatible with 64-bit versions of CentOS 7 and 8. To install KernelCare.ePortal, start with the minimal image of EL7 or EL8.

For installation and workability of ePortal the Nginx web server is required. We recommend to use stable version from the official Nginx repository:

$ cat > /etc/yum.repos.d/nginx.repo <<EOL
name=nginx repo

You can find more information at

Setup KernelCare.ePortal repo:

$ cat > /etc/yum.repos.d/kcare-eportal.repo <<EOL
name=KernelCare ePortal

Install KernelCare.eportal:

$ yum install -y kcare-eportal

How to adjust proxy on ePortal machine

On the ePortal machine, you should define the same proxy settings as you use in the command line.

To do so, add PROXY = '' to the following file: /usr/share/kcare-eportal/config/

If this file doesn't exist, create it with a NGINX owner:

echo "PROXY = ''" > /usr/share/kcare-eportal/config/
chown nginx:nginx /usr/share/kcare-eportal/config/

Restart ePortal (see Stopping & Starting section, choose a corresponding OS).

Managing Users

You can manage portal using /usr/bin/kc.eportal utility:

-l --list-users list all users
-a --add-user add a user
-d --delete-user delete a user
-c --change-password change a user password
-p --password provide a password for a user
-h --help show this help

To add a user:

$ kc.eportal -a admin -p AdminPassword

To change user's password:

$ kc.eportal -c admin -p NewPassword

Authorization using LDAP

If you are using ePortal but would like to restrict access for a specific user group then LDAP authorization allows you to check if a user is a member of that specific group. LDAP search query determines if a user is a member of a group with allowed access. Moreover, when using group authorization you need to make sure that a user with a specific DN is a member of that allowed access group.

For example, if you’d like to allow access to ePortal server for the users from the mathematicians group, you might have a configuration like this:

URL: ldap:// 
Filter: dc=example,dc=com??sub?(&(ou=mathematicians)(uniqueMember=uid=%s,dc=example,dc=com)) 
Connection string: uid=%s,dc=example,dc=com 

To make any user with any DN to have access to the ePortal server, you might have a configuration like this:

URL: ldap:// 
Connection string: uid=%s,dc=example,dc=com


  • ldap:// — a verified encrypted (TLS) connection;
  • ldaps:// — an SSL connection.


  • dc=example,dc=com??sub?(&(ou=mathematicians)(uniqueMember=uid=%s,dc=example,dc=com))

    Filter could be empty as ePortal uses this filter to make a search after LDAP bind (if the result is not empty, the user is authorized).

Connection String (DN template)

  • uid=%s,dc=example,dc=com

    Must contain login placeholder (%s).

You can use URL to adjust security and timeout parameters

  • strict_check=0 — to disable strict certificate check (enabled by default);
  • tls=0 — to disable TLS (enabled by default);
  • timeout=30 (in seconds, 5 by default).

For example, the URL with the security parameters:



  • You could use %s in both Connection String and Filter fields as a placeholder for user login.
  • Each LDAP implementation has its own peculiar properties, so we cannot provide any specific information about LDAP URL configuration because it depends entirely on the exact LDAP server configuration.


Log in to ePortal with your LDAP credentials

When you log in to ePortal with your LDAP credentials for the first time, a user with LDAP username, read-only permissions, and LDAP description is created in the database by default (https://<eportal>/admin/user/).

In the picture, you can see one user created with kc.eportal command line interface and two users logged in with LDAP credentials.

To set this LDAP user administrator permissions, set read-only=False (edit access required).

Is there a difference between local users and LDAP users?

The difference is in the login procedure. Login and password for a local user are saved in the local database but for an LDAP user, only login and permission are saved in the local database and authorization proceeds via LDAP server.

When a user logs in to ePortal, ePortal checks the user credentials in the local database at first. If the credentials are found, the user will be authorized, and only if the user credentials are not found, ePortal redirects to LDAP.

Accessing ePortal

To access KernelCare.eportal management console, connect to: https://YOUR_IP/admin

And enter your login & password

You can manage your login information using kc.eportal tool.

PatchSet Deployment


ePortal v0.8+

KernelCare.ePortal has built-in mechanism to download latest patches. To start using it, click Patch Source link in KernelCare.ePortal navigational bar and then click Settings. To get access to the Patch Source, please contact and request your Patch Source access credentials.

Once you set up patch source access info, you will get to a list of available patchsets. You can always go back and change your access info by clicking the Source link.

Clicking on [changelog] will provide changelog for given patchset. Clicking on [enable this patch, and all before it] will download and deploy this patchset and all the patchsets above. It is impossible to deploy patchsets out of order.

Clean obsolete releases

The list of provided patches is reduced once in a month (old patches that have newer versions are removed), but resources are not deleted from ePortal machine. The control of resource deletion is in charge of the ePortal administrator. To free disk space on ePortal old release resources could be removed.

To check what releases will be removed:

DRY_RUN=1 kc.eportal --clean-releases

To remove obsolete releases:

kc.eportal --clean-releases

Managing Keys

To register new servers you need to create a KernelCare key that will be used for server registration. To go to the list of keys, click the KernelCare ePortal logo at the top left.

  • To edit a key, click . The Edit tab opens.
  • To remove a key, click . Please note, that removing the key would remove all servers under that key.
  • Click a key to go to Servers tab with the list of servers registered under that key. You can also remove servers on that tab.

To create a new registration click Create tab. Fill in the following fields:

  • Key —  you can provide a key name or leave the field empty, so an automatically generated name will be used
  • Description — you can provide a description for the key
  • Server Limit — the amount of servers that can be registered under that key
  • Feed — select a specific feed or leave empty.

Click Save to add the key. The new registration key will be created and added to the list. The key itself will be used as a part of the registration command on an individual server.

Click Save and Add Another to save this key and add one more key.

Click Save and Continue Editing to add the key and open the key edit tab.

Click Cancel to return to the key list tab without adding a new key.

Managing Servers

You can see servers belonging to the key by clicking on the key itself in Managing Keys interface.

The screen shows servers registered under the key, their IP, hostname, effective kernel as well as the time of registration and last check in.

Managing Script


If scripts do not work on your ePortal, you might need to update ePortal first. To update ePortal, please run the following command:

> yum update kcare-eportal

To view the list of all servers IDs that are connected to the particular key, do the following:

  • In the UI go to the page with the list of keys. Then click the particular key. The list of servers connected to this key will be displayed.

To view the list of all servers IDs that are not connected to any key, use the Servers button on the navigation bar.

Script to unroll patchsets

To unroll patchset, run:

> kc.eportal --unroll 16012017_1

Script to determine the number of servers under the management of ePortal, per key

To see pairs of key/number of servers run:

> kc.eportal --list-servers
Count Key
0 2shcolu7Y1x6885Q
2 6J89aS44j6OmTr05

Script to automatically install latest patchsets

It determines if latest patches are available and installs them to the default feed.

>kc.eportal --get-latest

If you need to update other feeds that are marked for auto update instead of the default one, use a different argument:

>kc.eportal --auto-update

Note, that the latter command will update only feeds that meet the "deploy after" criteria.

Script to deploy patchset from a file

If you have no opportunity to connect your ePortal server to the KernelCare patch server, you can install it manually:

  • download the selected patchset to your ePortal server:
rsync -v 04082020_1.tgz your-eportal:/tmp
  • run the deployment tool with patchset file name as a parameter. It should be the full path to the file:
>kc.eportal --deploy /tmp/04082020_1.tgz

Unroll patches from UI

In the patch-source page, there is a list of available patches. To unroll patches click the button Roll back this patch, and all after it. Use it to roll back the patch and all the following patches.

Show extended check-in statistics in admin UI

A new table is added to the starting page. This table displays the following:

  • Total number of servers.
  • Number of servers that checked in for the past 48 hours.

The number of servers for each key is listed in the Key Inventory table.

Ability to create read-only users

[root@localhost ~]# kc.eportal -l
Num | Username
--- + --------------------------------
 1 | admin
 2 | user
[root@localhost ~]# kc.eportal -r user
User 'user' is now readonly

Feed Management

Feeds are intended to manage patchsets on the server, and they provide a possibility to bind a set of patches to a specific key. Possible use cases: for preliminary testing of patches, for applying updates to groups of servers with the similar hardware, etc.

To get into Feeds Management interface go to Settings → Feeds:

On this page a user can manage the existing feeds: create, delete, edit.

Available options:

  • Name — a name of a feed.
  • Auto update — enable and disable automatic downloading of patches to this feed.
  • Deploy after X hours — a delay in hours between the moment the patchset is available for deployment and the moment it is installed to the feed.

Every 10 minutes ePortal checks for new patches on the main patch server. If a new patch is available, it is uploaded to the ePortal server. Note: it is uploaded but is not deployed. The patch availability time is considered starting from the moment a new patch appears on the ePortal, and that time is taken into account in Deploy after X hours option. So, if a user sets Deploy after X hours = 10, the patch will be deployed to the feed 10 hours after it has been downloaded to the ePortal server.

To make the feed auto-update immediately (so that, new patches are loaded to the feed immediately after they are available on ePortal), set Deploy after X hours = 0.

A special case is a clean installation when ePortal is installed on a new server (there aren't any downloaded archives with patches and feeds with deployed patchsets, including default feed). In this case, if a user creates a new feed and sets Deployed after X hours option right away, then all patches (from the oldest to the latest available) will be deployed to the feed after the specified X hours. This is because the archives are downloaded from scratch and will be considered as “just appeared on ePortal” — that is, all patches will have the same appearance time on ePortal from which the option Deploy after X hours will repel.

On the main ePortal page, a user can set the corresponding key <> feed pair. This is done in the key creation interface or when editing a key.

By default, a new key is bound to the default feed, alternatively, a user can choose a desired feed from the drop-down menu.


When removing a feed all keys attached to this feed will be moved to the default feed.

Adding extra Tag field

To add an extra Tag field for the server, run:

kcarectl --tag command

where command is a parameter defined by a user. This parameter will be displayed in UI for the server. User could add multiple tags for each server. Each tag should be separated with ; symbol.


kcarectl --tag "env:prod;ubuntu"

This server has two tags : env:prod and ubuntu.

env:prod is a parameter that has tag name env and the value prod.

To remove all tags from a particular server, run:

kcarectl --tag ""

Where "" is a parameter to delete the previously defined tag.

How to setup ePortal to use HTTPS

Some assumptions for a server where e-portal is deployed:

  1. A firewall is disabled for 443 port.
  2. Private and public keys are downloaded on the server.
  • Edit ssl configuration template according to your certificates:
mv /etc/nginx/eportal.ssl.conf.example /etc/nginx/eportal.ssl.conf
vi /etc/nginx/eportal.ssl.conf
  • Include this configuration into the main one:
sed -e '3iinclude eportal.ssl.conf;' -i /etc/nginx/conf.d/eportal.conf
  • Restart nginx:
service nginx restart

In order to communicate with e-portal, updated to https, you need to modify KernelCare config files on all the servers if they have IPs hardcoded servers settings.

To do that, update PATCH_SERVER and REGISTRATION_URL environment variables:

vi /etc/sysconfig/kcare/kcare.conf

So, after editing your /etc/sysconfig/kcare/kcare.conf should contain updated PATCH_SERVER and REGISTRATION_URL environment variables like in the example below:


The following example demonstrates how to connect new servers to e-portal configured for https:

$ export KCARE_PATCH_SERVER=https://eportal_domain_name/
$ export KCARE_REGISTRATION_URL=https://eportal_domain_name/admin/api/kcare
$ export
$ curl -s | bash
$ /usr/bin/kcarectl --register key_from_your_eportal

Deploying KernelCare

To deploy kernelcare client software to use ePortal, the following environment variables should be setup prior to RPM install:

Environment Variable Value Description
KCARE_PATCH_SERVER http://eportal_ip/ URL to a server from which patches will be downloaded
KCARE_REGISTRATION_URL http://eportal_ip/admin/api/kcare URL to ePortal's api
KCARE_MAILTO [2.5+] email@address Email to receive all notifications related to failed KernelCare updates. Used in /etc/cron.d/kcare-cron


$ export
$ curl -s | bash
$ kcarectl --register r72fF838Q47oWigj

KernelCare client config file

KernelCare client configuration file is located in /etc/sysconfig/kcare/kcare.conf



If AUTO_UPDATE set to True, KernelCare client will check in every 4 hours, and try to download and apply latest patches

PATCH_SERVER - server from which patches will be downloaded

REGISTRATION_URL - URL used to register/unregister server

Deployment Automation

It is possible to use automation tools like Ansible/Puppet/Chef/Salt to install and operate KernelCare on a big number of systems.

The deployment process includes:

  • downloading and running the KernelCare agent installation script
  • updating /etc/sysconfig/kcare/kcare.conf with ePortal-related entries
  • registering KernelCare agents using an activation key


To start the automated deployment, you need to specify the following information:

  • ePortal server name (or IP) in the eportal_srv Ansible variable. Other config file options can be found at Config Options and KernelCare client config file (ePortal).
  • an activation key in the activation_key Ansible variable. Activation keys can be generated in ePortal as described in Managing Keys (ePortal).

Ansible playbook for deployment phase may look like:

- hosts: kernelcare
    activation_key: 89gRVCp1rY0ZQ053
  - name: Download the installation shell script
      url: "{{ eportal_srv }}/installer"
      dest: /root/
      mode: '0700'

  - name: Run the installation shell script
    shell: /root/ >> /var/log/kcare_install.log
      KCARE_REPO: "{{ eportal_srv }}/repo"

  - name: Update kcare.conf with ePortal configuration
      path: /etc/sysconfig/kcare/kcare.conf
      create: yes
      block: |
        PATCH_SERVER={{ eportal_srv }}/
        REGISTRATION_URL={{ eportal_srv }}/admin/api/kcare

  - name: register KernelCare agents
    command: /usr/bin/kcarectl --register {{ activation_key }}

Ansible playbook file example for KernelCare agent removal:

- hosts: kernelcare
    - name: unregister KernelCare agents
      command: /usr/bin/kcarectl --unregister
      ignore_errors: yes
        removes: /usr/bin/kcarectl

    - name: remove kernelcare package
        name: kernelcare
        state: absent

Changing ePortal IP

You can change ePortal IP at any moment, but you need to modify KernelCare config files on all the servers if they have IPs hardcoded.

To do that, edit: /etc/sysconfig/kcare/kcare.conf



To point to the right location.

Configuration & locations

Web Server (nginx) configuration is located at /etc/nginx/conf.d/eportal.conf

Database (sqlite) is stored in /usr/share/kcare-eportal/data.sqlite To reset database:

$ mv /usr/share/kcare-eportal/data.sqlite /usr/share/kcare-eportal/data.sqlite_backup
$ cd /usr/share/kcare-eportal && python

Client access data file used to decide if server has access to the patches is stored in /usr/share/kcare-eportal/kcare_servers.htpasswd

Patches are stored in: /usr/share/kcare-eportal/patches

Stopping & Starting

KernelCare.ePortal on EL7

To stop/start/reload/restart configuration of nginx server:

$ systemctl stop|start|reload|restart nginx

To stop/start/restart ePortal (Python):

$ systemctl stop|start|restart eportal

Log Files

ePortal log: journalctl -u eportal

Nginx ePortal access log: /var/log/nginx/access.log

Nginx error log: /var/log/nginx/error.log

Log Rotation

By default there is no predefined parameters for eportal's logs rotation. If you want to enable it for the files listed above:

  • Install logrotate package
  • Create/edit /etc/logrotate.d/eportal configuration file

Example logrotate config:

/var/log/nginx/kcare-eportal.log {
    rotate 5 # keep 5 last archives
    missingok # it's ok if there is no such file
    notifempty # do nothing if file is empty

Nagios & Zabbix support

KernelCare.ePortal since version 1.2 supports server monitoring similar to Nagios & Zabbix monitoring.

You can curl the API directly to receive the information:


or you can use script by modifying KEY_KCARE_NAGIOS_ENDPOINT in it to point to your server (change (link to old UI) or (link to new UI) with https://yourserver/admin ).


Access using PARTNER_LOGIN/TOKEN is not supported by KernelCare.ePortal.

Usage reports

In common case, usage reports are sending automatically but when it's not possible, ePortals will try to send report as an email. That requires configured Sendmail (SSMTP) on the host. You can find a short instruction below.

If mail sending attempt fails, ePortal will save the reports in /usr/share/kcare-eportal/reports which should be sent manually.

How to configure Sendmail (SSMTP)

First of all you need to install ssmtp:

yum install -y ssmtp

Edit /etc/ssmtp/ssmtp.conf file in accordance with your SMTP server configuration. Here is a simple config file describing a common way to connect to Gmail accounts:

Actual location of a TLS_CA_Files depends on distrib:

"/etc/ssl/certs/ca-certificates.crt",                // Debian/Ubuntu/Gentoo etc.
"/etc/pki/tls/certs/ca-bundle.crt",                  // Fedora/RHEL 6
"/etc/ssl/ca-bundle.pem",                            // OpenSUSE
"/etc/pki/tls/cacert.pem",                           // OpenELEC
"/etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem", // CentOS/RHEL 7

Also you could get if from:

curl-config --ca

Now you can test a connection:

echo -n 'Subject: test\n\nTesting ssmtp' | sendmail -v

Custom environment variables

You can define your own environment variables for ePortal process.

There is the /usr/share/kcare-eportal/environment folder, which is basically daemon tools compatible envdir.

For example, to disable the default https verification you can set the PYTHONHTTPSVERIFY environment variable to 0 as follows:

echo 0 > /usr/share/kcare-eportal/environment/PYTHONHTTPSVERIFY`