Here is how logs look like after this (and sure after configuring your server’s ip as a syslog server on the remote device). Most likely they will appear in /var/log/syslog :
Nov 25 15:39:19 10.11.13.102 [1: 0]RTP Tx Dn Nov 25 15:39:19 10.11.13.102 [1: 0]ENC INIT 8 Nov 25 15:39:19 10.11.13.102 [1: 0]RTP Tx Up (pt=8->0a48000a:18076) Nov 25 15:39:19 10.11.13.102 CC: Remote Resume Nov 25 15:39:19 10.11.13.102 CC: Connected Nov 25 15:39:19 10.11.13.102 RTP: SSRC changed 787a1882->1df25275 Nov 25 15:39:29 10.11.13.102 syscfg_update_hdlr!!! Nov 25 15:39:29 10.11.13.102 syscfg_update_hdlr!!! Nov 25 15:39:51 10.11.13.102 syscfg_update_hdlr!!!
To redirect logs from remote host with ip address 10.11.13.102 do the following:
Create /etc/rsyslog.d/11-linksys-gw.conf with the following lines:
if $fromhost-ip == '10.11.13.102' then /var/log/linksys-gw.log & stop
Create /var/log/linksys-gw.log empty file. At least in Debian you need to chown root:adm for this file.
Finally, restart rsyslog daemon. After that all logs going from remote ip-address 10.11.13.102 will be stored in a separate file.
Trying to start VM from console, but unsuccessful:
lexus@lexus-H110M-S2H:~$ vboxmanage startvm 21eaceac-f85e-4622-a52b-c586352aa9eb
Waiting for VM "21eaceac-f85e-4622-a52b-c586352aa9eb" to power on...
VBoxManage: error: The virtual machine 'centos7-ast-16' has terminated unexpectedly during startup because of signal 6
VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component MachineWrap, interface IMachine
The solution is "--type headless" option:
lexus@lexus-H110M-S2H:~$ vboxmanage startvm 21eaceac-f85e-4622-a52b-c586352aa9eb --type headless
Waiting for VM "21eaceac-f85e-4622-a52b-c586352aa9eb" to power on...
VM "21eaceac-f85e-4622-a52b-c586352aa9eb" has been successfully started.
Imagine the situation when there is some remote host machine with several VMs. You have an SSH access to host machine, but no VNC to manage easily those VMs, even doing the most elementary actions.
Now I would like to get the IP address of some VM. But there is no any way to do it until we use GuestAdditions. I mean that you’ve already started your VM with the appropriate console command and now need to log in via SSH, but you don’t know it’s IP address (e.g. in case of bridged network settings of the VM).
To be able to see VM’s IP address from host’s machine console, you have to install VitualBox to your guest machine. Then you need to “insert” an .iso containing GuestAdditions to your guest machine (the easiest way is to do it using VirtualBox GUI, but I’m sure there is also a console command).
If the VM’s cd-rom with this .iso is not mounted automatically, do it manually:
[root@flexisip ~]# mount /dev/cdrom /mnt/cdrom/
After that the .iso’s files are available:
[root@flexisip cdrom]# ls -l /mnt/cdrom/
total 47008
-r--r--r--. 1 root root 763 feb 20 2020 AUTORUN.INF
-r-xr-xr-x. 1 root root 6384 jan 14 2022 autorun.sh
dr-xr-xr-x. 2 root root 792 jan 14 2022 cert
dr-xr-xr-x. 2 root root 1824 jan 14 2022 NT3x
dr-xr-xr-x. 2 root root 2652 jan 14 2022 OS2
-r-xr-xr-x. 1 root root 4821 jan 14 2022 runasroot.sh
-r--r--r--. 1 root root 592 jan 14 2022 TRANS.TBL
-r--r--r--. 1 root root 4029558 jan 14 2022 VBoxDarwinAdditions.pkg
-r-xr-xr-x. 1 root root 3949 jan 14 2022 VBoxDarwinAdditionsUninstall.tool
-r-xr-xr-x. 1 root root 7474611 jan 14 2022 VBoxLinuxAdditions.run
-r--r--r--. 1 root root 9439232 jan 14 2022 VBoxSolarisAdditions.pkg
-r-xr-xr-x. 1 root root 16895432 jan 14 2022 VBoxWindowsAdditions-amd64.exe
-r-xr-xr-x. 1 root root 270840 jan 14 2022 VBoxWindowsAdditions.exe
-r-xr-xr-x. 1 root root 10000520 jan 14 2022 VBoxWindowsAdditions-x86.exe
-r--r--r--. 1 root root 259 oct 4 2021 windows11-bypass.reg
Now we need to install GuestAdditions to the guest machine (VM):
[root@flexisip ~]# cd /mnt/cdrom
[root@flexisip cdrom]# sh ./VBoxLinuxAdditions.run
Verifying archive integrity... All good.
Uncompressing VirtualBox 6.1.32 Guest Additions for Linux........
VirtualBox Guest Additions installer
Copying additional installer modules ...
Installing additional modules ...
VirtualBox Guest Additions: Starting.
VirtualBox Guest Additions: Building the VirtualBox Guest Additions kernel
modules. This may take a while.
VirtualBox Guest Additions: To build modules for other installed kernels, run
VirtualBox Guest Additions: /sbin/rcvboxadd quicksetup <version>
VirtualBox Guest Additions: or
VirtualBox Guest Additions: /sbin/rcvboxadd quicksetup all
VirtualBox Guest Additions: Building the modules for kernel
3.10.0-1160.88.1.el7.x86_64.
And now you can see VM’s IP address from your host machine console (NAT network settings):
alexey@amd:~$ VBoxManage guestproperty get centos-flexisip "/VirtualBox/GuestInfo/Net/0/V4/IP"
Value: 10.0.2.15
The same for bridged networking:
alexey@amd:~$ VBoxManage guestproperty get centos-flexisip "/VirtualBox/GuestInfo/Net/0/V4/IP"
Value: 192.168.88.239
Main idea: 1) update kernel, 2) add RPM Fusion repository and install ffmpeg from it.
If trying to compile RTPEngine 10 in CentOS 7 with ffmpeg installed from some other repository (e.g. nux-desktop, as I had) – you’ll get an error! (see screenshot)
Update kernel (my system had 3.10.0-957.el7.x86_64 after installation):
[root@localhost ~]# uname -a
Linux localhost.localdomain 3.10.0-957.el7.x86_64 #1 SMP Thu Nov 8 23:39:32 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# cat /etc/centos-release
CentOS Linux release 7.6.1810 (Core)
Updated to the newest available from standard repository (3.10.0-1160.59.1.el7.x86_64):
yum --showduplicates list available kernel.x86_64
yum install kernel-3.10.0-1160.59.1.el7
reboot
[root@localhost ~]]# uname -a
Linux localhost.localdomain 3.10.0-1160.59.1.el7.x86_64 #1 SMP Wed Feb 23 16:47:03 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Then disable nux-desktop (if you previously installed ffmpeg from it) repository (‘enabled=0’ in /etc/yum.repos.d/nux-dextop.repo).
Ensure that ffmpeg and ffmpeg-devel now are available from just added RPM Fusion repository and install them (you’ll see repo name in the yum output, not shown here):
yum --showduplicates list available ffmpeg
yum check-update
yum install ffmpeg ffmpeg-devel
Then create build directory structure (use rpmbuild tool).
This guide will help you to understand how OpenSIPS can be monitored with Zabbix, sharing its statistic data via HTTP interface in JSON format. This article assumes using OpenSIPS 3.2 and Zabbix 6.
The official documentation does not have other more complicated examples, e.g. “get_statistics sl:”, that’s why I decided to write this article, maybe it’s more about JSON, JSONPath and working with all this in Zabbix.
As an example, we’ll get stateless replier module statistics, like shown by invoking a CLI command “opensips-cli -x mi get_statistics sl:” .
OpenSIPS will answer and you’ll see SL module statistics after sending this request with CURL.
But the responce is a one-liner, so we need to convert this one line to JSON format and then to create a JSONPath, to be able to extract the value we need.
Let’s monitor not all SL module statistics received from OpenSIPS, but the number of 2xx replies only.
Now it’s time to add items to your OpenSIPS host in Zabbix. Item parameters:
Type: HTTP Agent
Type of information: Numeric (unsigned)
Request type: POST
Request body type: JSON data
Request body: {"jsonrpc": "2.0", "id": "1", "method": "get_statistics", "params": {"statistics": ["sl:"]}}
Retrieve mode: Body
Convert to JSON (enabled)
Screenshots as usual:
Item Preprocessing parameters:
1st step - JSONPath
Parameters: $.body.result.["sl:2xx_replies"]
Type of information: Numeric (unsigned)
Screen – item Preprocessing and successful testing:
Now we add a graph with this item (I hope you know how to create graphs in Zabbix) and it’s time to test. I will generate thousands of OPTIONS requests to my OpenSIPS with the sipp tool (I also recommend this sipp cheatsheet).
Download OPTIONS.xml scenario file, and generate 10000 OPTIONS requests with call rate of 10 (I assume that your OpenSIPS, like mine, answers “200 OK”):
Users add themselves as queue members by dialing some short number (AddQueueMember dialplan app is used). The queue may contain several dynamic members.
The task is to remove all queue members by dialing some number, no matter how much members are in this queue. Queue name is ‘superQueue’ (example for AEL, Asterisk 13):
// remove all dynamic queue members
0000 =>
{
NoOp(superQueue member list: ${QUEUE_MEMBER_LIST(superQueue)});
// count members of a queue
count=${QUEUE_MEMBER(superQueue,count)};
// and remove all, one by one
while (${count} >= 1) {
Set(QMLsuperQueue=${QUEUE_MEMBER_LIST(superQueue)});
Set(kicked=${CUT(QMLsuperQueue,\,,1)});
Log(NOTICE, removing dynamic member: ${kicked});
RemoveQueueMember(superQueue,${kicked});
count=${count}-1;
}
Hangup();
};
voip ~ # journalctl --disk-usage Archived and active journals take up 4.2G on disk.
voip ~ # du -sh /var/log/journal/ 4,3G /var/log/journal/
Let’s leave 500M of logs only:
voip ~ # journalctl --vacuum-size=500M … Vacuuming done, freed 3.5G of archived journals on disk.
Check once again:
voip ~ # journalctl --disk-usage Archived and active journals take up 744.2M on disk. voip ~ # voip ~ # du -sh /var/log/journal/ 745M /var/log/journal/
