AJN's questions

Exim is configured on a newly provisioned VM from a public cloud provider with public IPs (scaleway.net)

Purpose:

Be able to send mails from CLI (or scripts) to public destination recipients (gmail,yahoo,...)

Results:

Exim4 log file /var/log/exim4/mainlog shows "Connection timeout" with all tested servers (gmail, free.fr, online.net)

Configuration details:

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.5 LTS
Release:    16.04
Codename:   xenial

• No firewalls configured on the server and no rules from the cloud provider.
• The resolved smtp servers IP addresses (from exim log file) are pingable.

Tested with different smtp servers: (gmail, free.fr, online.net)

cat /etc/exim4/update-exim4.conf.conf

# /etc/exim4/update-exim4.conf.conf
#
# Edit this file and /etc/mailname by hand and execute update-exim4.conf
# yourself or use 'dpkg-reconfigure exim4-config'
#
# Please note that this is _not_ a dpkg-conffile and that automatic changes
# to this file might happen. The code handling this will honor your local
# changes, so this is usually fine, but will break local schemes that mess
# around with multiple versions of the file.
#
# update-exim4.conf uses this file to determine variable values to generate
# exim configuration macros for the configuration file.
#
# Most settings found in here do have corresponding questions in the
# Debconf configuration, but not all of them.
#
# This is a Debian specific file

dc_eximconfig_configtype='smarthost'
dc_other_hostnames=''
dc_local_interfaces='127.0.0.1 ; ::1'
dc_readhost=''
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='smtp.online.net::587'
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname='false'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool

Accounts and passwords correctly configured for each test with smtp server:

cat /etc/exim4/passwd.client

#gmail-smtp.1.google.com:[email protected]:pass1
#smtp.online.net:[email protected]:pass2
smtp.free.fr:[email protected]:pass2

root@scw-5c50c6:~# tail -f /var/log/exim4/mainlog

root@scw-5c50c6:~# tail -f /var/log/exim4/mainlog
2018-10-27 17:32:47 1gGSDM-0002ib-5Y == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host
2018-10-27 17:32:47 1gGSKT-0002sr-C6 == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host
2018-10-27 17:32:47 1gGSF6-0002ij-UA == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host
2018-10-27 17:32:47 1gGSJs-0002no-EM == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host
2018-10-27 17:32:47 1gGSHC-0002is-0H == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host
2018-10-27 17:32:47 End queue run: pid=12074
2018-10-27 17:32:53 1gGSQA-00038q-A1 H=smtpauth-dc2.online.net [62.210.16.40] Connection timed out
2018-10-27 17:32:53 1gGSQA-00038q-A1 == [email protected] R=smarthost T=remote_smtp_smarthost defer (110): Connection timed out

2018-10-27 17:47:12 1gGSg4-00039P-CW <= root@localhost U=root P=local S=369
2018-10-27 17:47:12 1gGSg4-00039P-CW == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host


2018-10-27 18:02:34 1gGSst-0003JZ-5k H=smtp.free.fr [212.27.48.4] Connection timed out
2018-10-27 18:02:34 1gGSst-0003JZ-5k == [email protected] R=smarthost T=remote_smtp_smarthost defer (110): Connection timed out
2018-10-27 18:03:09 1gGSvV-0003KT-9k <= root@localhost U=root P=local S=369
2018-10-27 18:03:09 1gGSvV-0003KT-9k == [email protected] R=smarthost T=remote_smtp_smarthost defer (-53): retry time not reached for any host

Am I missing something in the configs?

Linux environment: Debian, Ubuntu, Centos

Goal:
Test monitoring program that set alarms and trigger different alarms at different cpu percentages.
ex: (30-50%), (51-70%) and >90%

So I need a cpu stresser that can simulate specific cpu percentage per core.
stress-mg looks like the most advanced.

According to its documentation http://kernel.ubuntu.com/~cking/stress-ng/ it is possible to set load values between 0 and 100%:

-l P --cpu-load P load CPU by P %, 0=sleep, 100=full load (see -c)

stress-ng -c 1 -p 30

stress-ng: info: [12650] dispatching hogs: 0 I/O-Sync, 1 CPU, 0 VM-mmap, 0 HDD-Write, 0 Fork, 0 Context-switch, 30 Pipe, 0 Cache, 0 Socket, 0 Yield, 0 Fallocate, 0 Flock, 0 Affinity, 0 Timer, 0 Dentry, 0 Urandom, 0 Float, 0 Int, 0 Semaphore, 0 Open, 0 SigQueue, 0 Poll

Undesired result:
But it doesn't seem to work, aLL cores are hogged at 100%

Any ideas how to achieve this?

I am testing haproxy with keepalive to 3 servers.
Haproxy server configurations work fine (USLTS4/USLTS5), but not keepalived.

The process started on both haproxy's, but the VIP is not assigned to the master (USLTS4), so not reachable from clients.

Here are haproxy and keepalived configs:

haproxy

keepalived

Both haproxy's work fine separately and loadbalance traffic

USLTS4:~$ netstat -nlta | grep :80 tcp 0 0 0.0.0.0:80
0.0.0.0:* LISTEN

USLTS5:~$ netstat -nlta | grep 80 tcp 0 0 0.0.0.0:80
0.0.0.0:* LISTEN

No VIP assigned to the main haproxy

Tested with unicast and multicast (default) configurations.

unicast_peer { 
192.168.20.254
}

To generate an SSL certificate file for Apache, I am using the below command:

 openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/apache2/ssl/apache.key -out /etc/apache2/ssl/apache.cert

And I manually feed it with these parameters:

Country Name (2 letter code) [AU]:AU
State or Province Name (full name): Myname
[Some-State]:Some-State
Locality Name (eg, city) []:City
Organization Name (eg, company) [Internet Widgits Pty Ltd]:Internet
Organizational Unit Name (eg, section) []:Section
Common Name (e.g. server FQDN or YOUR name) []:yourname
Email Address []:[email protected]

Is it possible to enter them from a file or right from an OpenSSL command line using options?

There is no hint from the OpenSSL man pages.