> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/tmedia-documentation/server-and-os-administration/syslog-redirect.md).

# Syslog redirect

This procedure enables successful and failed login attempts to the TMG unit to be sent to an external syslog server.

### Prerequisites

To implement this, you need to remove the direct access to the web portal from your firewall, so that the TMG unit must now be accessed through the SSH port, and the web portal with SSH tunneling.

We use the standard linux syslog to also send cron and messages to the syslog server, so the syslog sever needs to be Centos OS

### Notes

The default UDP port for the syslog server is 514 and this procedure redirects it to port 1524.

Change the hostname of the syslog server accordingly. In the procedure below, the hostname if the syslog server is : *lab\_syslog\_server* .

This procedure works for a standalone system. To allow 1+1 systems, please add the tcp port 3306 in the iptables for the database access.

### Procedure For Syslog redirect

#### Make sure mgmt0 is available and active

Connect to SSH interface: [Connect to SSH](https://github.com/telcobridges-main/tmedia-wiki/tree/main/tmedia/operations/accessing-device/README.md)

Then do these commands ifconfig -a mgmt0;ethtool mgmt0 Output: mgmt0 Link encap:Ethernet HWaddr 00:34:45:94:E3:F7 inet addr:10.10.10.10 Bcast:10.10.10.1 Mask:255.255.255.0 ... Settings for mgmt0: ... Link detected: yes If mgmt0 does not exist, we need to modify the procedure for this port. Please contact **TelcoBridges support**.

#### Check if some firewall rules exist already

```
iptables -L -v; iptables -t nat -L -n -v
```

Example of an empty table: Chain INPUT (policy ACCEPT 602M packets, 157G bytes) pkts bytes target prot opt in out source destination Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 614M packets, 144G bytes) pkts bytes target prot opt in out source destination Chain PREROUTING (policy ACCEPT 1841K packets, 596M bytes) pkts bytes target prot opt in out source destination Chain INPUT (policy ACCEPT 1222K packets, 478M bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 13M packets, 4814M bytes) pkts bytes target prot opt in out source destination Chain POSTROUTING (policy ACCEPT 13M packets, 4814M bytes) pkts bytes target prot opt in out source destination

If some rules exist, we have to know why they are active and if they need to remain there. Please contact **TelcoBridges support**.

#### Firewall rules to the management port

Apply these firewall rules on the SSH interface. These rules include SSH, ICMP, DNS, SNMP and Port redirection (514 -> 1524): iptables -P INPUT ACCEPT iptables -F iptables -N TMG-Firewall-All iptables -A TMG-Firewall-All -p tcp --dport 22 -j ACCEPT iptables -A TMG-Firewall-All -p icmp -j ACCEPT iptables -A TMG-Firewall-All -p udp --sport 53 -j ACCEPT iptables -A TMG-Firewall-All -p udp --dport 53 -j ACCEPT iptables -A TMG-Firewall-All -p udp --dport 161 -j ACCEPT iptables -A TMG-Firewall-All -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -A TMG-Firewall-All -j DROP iptables -A INPUT -i mgmt0 -j TMG-Firewall-All iptables -t nat -A OUTPUT -p udp --dport 514 -j DNAT --to-destination :1524 service iptables save service iptables restart

**Verify firewall rules**

```
iptables -L -v; iptables -t nat -L -n -v
```

Final firewall output: Chain INPUT (policy ACCEPT 685K packets, 303M bytes) pkts bytes target prot opt in out source destination 2441 390K TMG-Firewall-All all -- mgmt0 any anywhere anywhere Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 677K packets, 280M bytes) pkts bytes target prot opt in out source destination Chain TMG-Firewall-All (1 references) pkts bytes target prot opt in out source destination 380 27568 ACCEPT tcp -- any any anywhere anywhere tcp dpt:ssh 408 40586 ACCEPT icmp -- any any anywhere anywhere 25 2994 ACCEPT udp -- any any anywhere anywhere udp spt:domain 0 0 ACCEPT udp -- any any anywhere anywhere udp dpt:domain 0 0 ACCEPT udp -- any any anywhere anywhere udp dpt:snmp 90 10046 ACCEPT all -- any any anywhere anywhere state RELATED,ESTABLISHED 1538 309K DROP all -- any any anywhere anywhere Chain test (0 references) pkts bytes target prot opt in out source destination Chain PREROUTING (policy ACCEPT 2539 packets, 897K bytes) pkts bytes target prot opt in out source destination Chain POSTROUTING (policy ACCEPT 19007 packets, 7249K bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 19006 packets, 7249K bytes) pkts bytes target prot opt in out source destination 0 0 DNAT udp -- \* \* 0.0.0.0/0 0.0.0.0/0 udp dpt:514 to::1524

#### Add information to send to remote syslog

For successful/failed login, messages and cron info, edit this file: vim /etc/syslog.conf Add these lines in the file:

1. Send to remote syslog authpriv.*;*.info;cron.\* @lab\_syslog\_server Then restart the syslog service service syslog restart

If server hostname (syslog\_server) is unreachable, edit the hosts file: cat /etc/hosts And add this line to the file: \[IP of syslog server] syslog\_server e.g. 192.168.77.88 lab\_syslog\_server

#### Instructions to access the web portal with SSH tunneling

See these links for setup. Local port must be a free one and remote port will be 12358

[Tunneling with Secure CRT](https://www.vandyke.com/support/tips/socksproxy.html)

[Tunneling with Putty](http://realprogrammers.com/how_to/set_up_an_ssh_tunnel_with_putty.html)

[How to setup SSH tunnel with Putty](https://github.com/telcobridges-main/tmedia-wiki/tree/main/tmedia/operations/how-to-setup-ssh-tunnel-with-putty/README.md)

#### Test the process

Tail the file on the syslog server and access the unit with SSH: tail -f /var/log/secure you will see something like this: Nov 30 10:05:53 10.10.10.10 sshd\[3895]: Accepted password for root from 10.10.10.54 port 22501 ssh2

#### Other information

To activate reception of remote syslog on Server: cat /etc/sysconfig/syslog SYSLOGD\_OPTIONS="-m 0 -r" service syslog restart

If the remote syslog server is on the default port 514, remove this line from the iptables: iptables -t nat -A OUTPUT -p udp --dport 514 -j DNAT --to-destination :1524 To delete iptables rules: iptables -t nat -D OUTPUT 1 service iptables save service iptables restart

By default, access information will be sent to this file on the syslog server: /var/log/secure and system messages will be sent to this file: /var/log/messages


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://prosbcdocs.telcobridges.com/tmedia-documentation/server-and-os-administration/syslog-redirect.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.