Forward Syslog Options

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This dialog controls Syslog forwarding options.

 

 

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Forward Syslog Properties

 

Protocol Type

 

There are various ways to transmit syslog messages. In general,they can be sent via UDP, TCP or RFC 3195 RAW. Typically, syslog messages are received via UDP protocol, which is the default. UDP is understood by almost all servers, but doesn't guarantee transport. In plain words, this means that syslog messages sent via UDP can get lost if there is a network error, the network is congested or a device (like a router or switch) is out of buffer space. Typically, UDP works quite well. However, it should not be used if the loss of a limited number of messages is not acceptable.

 

TCP and RFC 3195 based syslog messages offer much greater reliabilty. RFC 3195 is a special standardized transfer mode. However, it has not receive any importance in practice. Servers are hard to find. As one of the very few, Adiscon products support RFC 3195 also in the server implementations. Due to limited deployment, however, RFC 3195 is very little prooven in practice. Thus we advise against using RFC 3195 mode if not strictly necessary (e.g. part of your requirement sheet).

 

TCP mode comes in three flavours. This stems back to the fact that transmission of syslog messages via plain TCP is not yet officially standardized (and it is doubtful if it ever will be). However, it is the most relevant and most widely implemented reliable transmission mode for syslog. It is a kind of unwritten industry standard. We support three different transmission modes offering the greatest compatibility with all existing implementations. The mode "TCP (one message per connection)" is a compatibility mode for Adiscon servers that are older than roughly June 2006. It may also be required for some other vendors. We recommend not to use this setting, except when needed. "TCP (persistent connection)" sends multiple messages over a single connection, which is held open for an extended period of time. This mode is compatible with almost all implementations and offers good performance. Some issues may occur if control characters are present in the syslog message, which typically should not happen. The mode "TCP (octet-count based framing)" implements algorithms of an upcoming (but not yet finalized) IETF standard. It also uses a persistent connection. This mode is reliable and also deals with embedded control characters very well. However, there is only a limited set of receivers known to support it. As of this writing (January 2007), there were no non-Adiscon receivers supporting that mode. We expect progress once the IETF standard is officially out.

 

As a rule of thumb, we recommend to use "TCP (octet-count based framing)" if you are dealing only with (newer) Adiscon products. Otherwise, "TCP (persistent connection)" is probably the best choice. If you select one of these options, you can also select a timeout. The connection is torn down if that timeout expires without a message beeing sent. We recommend to use the default of 30 minutes, which should be more than efficient. If an installation only occasionally sends messages, it could be useful to use a lower timeout value. This will free up connection slots on the server machine.

 

 

Syslog Server

 

This is the name or IP address of the system to which Syslog messages should be sent to. You can either use an IPv4, an IPv6 Address or a Hostname that resolves to an IPv4 or IPv6 Address.

 

 

Syslog Port

 

The remote port on the Syslog server to report to. If in doubt, please leave it at the default value of 514, which is typically the Syslog port. Different values are only required for special setups, for example in security sensitive areas. Set the port to 0 to use the system-supplied default value (which defaults to 514 on allmost all systems).

 

Instead of the port number, a service name can be used. If so, that name is looked up via the socket service database functions.

 

 

Use this backup syslog server if first one fails

 

The backup server is automatically used if the connection to the primary server fails. The primary server is automatically retried when the next Syslog session is opened. This option is only available when using TCP syslog.

 

 

Session Timeout

 

Timeout value for TCP persistent and octet-count based framing connections.

 

 

Syslog Message Options

 

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Syslog Message Options

 

Syslog processing

 

With this settings you can assign how your syslog messages will be processed.

For processing syslog you can choose out of four different options. You can use RFC3164 or RFC5424 (recommended) which is the current syslog standard, you are able to customize the syslog header or you do not process your syslog and forwards it as it is.

 

 

Custom Header Format

 

In this field you can specify the contents of your syslog header. This option is only available when you choose "Use Custom Syslog Header" in the Syslog Processing menu. The contents can be either a fixed message part which you can write into the field yourself or you use properties as dynamic content. By default the Header field is filled with the content of the RFC 5424 header.

 

Please note that the header content of the Header field can be configured. Event properties are described in the property replacer section.

 

 

Output Encoding

 

This setting is most important for Asian languages. A good rule is to leave it at "System Default" unless you definitely know you need a separate encoding. "System Default" works perfect in the far majority of cases, even on Asian (e.g. Japanese) Windows versions.

 

 

Used Message Format

 

You can use several different message formats for forwarding messages via syslog.

 

Use Custom Format

 

The custom format lets you decide how the content of a syslog message looks like. You can use properties to insert content dynamically or have fixed messages that appear in every message. Event properties are described in the property replacer section.

 

Use XML to Report

 

If this option is checked, the forwarded Syslog message is a complete XML-formatted information record. It includes additional information like timestamps or originating system in an easy to parse format.

 

The XML formatted message is especially useful if the receiving system is capable of parsing XML data. However, it might also be useful to a human reader as it includes additional information that cannot be transferred otherwise.

 

Forward as MW Agent XML Representation Code

 

MonitorWare supports a specific XML-Representation of the event. If it is checked, that XML representation is used. It provides additional information (like informationunit type, original source system, reception time & many more) but is harder to read by a human. At the same time, it is obviously easier to parse. Please note that this option is only "experimental" and is not an official standard.

 

Use CEE enhanced Syslog Format

 
If enabled, the new CEE enhanced Syslog format will be used (work in progress). All useful properties will be included in a JSON Stream. The message itself can be included as well, see the “Include message property in CEE Format” option. Here is a sample how the format looks like for a security Eventlog message:

 
@cee: {"source": "machine.local", "nteventlogtype": "Security", "sourceproc": "Microsoft-Windows-Security-Auditing", "id": "4648", "categoryid": "12544", "category": "12544", "keywordid": "0x8020000000000000", "user": "N\\A", "SubjectUserSid": "S-1-5-11-222222222-333333333-4444444444-5555", "SubjectUserName": "User", "SubjectDomainName": "DOMAIN", "SubjectLogonId": "0x5efdd", "LogonGuid": "{00000000-0000-0000-0000-000000000000}", "TargetUserName": "Administrator", "TargetDomainName": " DOMAIN ", "TargetLogonGuid": "{00000000-0000-0000-0000-000000000000}", "TargetServerName": "servername", "TargetInfo": " servername ", "ProcessId": "0x76c", "ProcessName": "C:\\Windows\\System32\\spoolsv.exe", "IpAddress": "-", "IpPort": "-", "catname": "Logon", "keyword": "Audit Success", "level": "Information", }

 

Additionaly to this format you can set Include message property in CEE Format

 

If enabled, the message itself will be included in the JSON Stream as property. Disable this option if you do not want the message itself in the CEE Format.

 

 

Please note you can also make Event ID part of the actual Syslog message while forwarding to a Syslog Server then you have to make some changes in the Forward Syslog Action. Click here to know the settings.

 

 

Message Format

 

You can change the message format. By default the original message is forwarded.

 

Please note that the message content of the Message field can be configured. Event properties are described in the property replacer section.

 

 

Add Syslog Source

 

If this box is checked, information on the original originating system is prepended to the actual message text. This allows the recipient to track where the message originally came from.

 

Please note: This option is not compatible with RFC 3164. We recommend selecting it primarily when message forwarding to a WinSyslog Interactive Server is intended.

 

 

Use zLib Compression to compress the data

With this option you can set the grade of compression for your syslog messages. For more information please read the note at the bottom of this page.

 

 

 

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SSL/TLS related Options

 

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SSL/TLS related Options

 

Enable SSL / TLS Encryption

 

If this option is enabled, the action will not be able to talk to a NON-SSL secured server. The method used for encryption is compatible to RFC5425 (Transport Layer Security (TLS) Transport Mapping for Syslog).

 

TLS Mode

 

Anonymous Authentication

Default option. This means that a default certificate will be used.

 

Use Certificate

If this option is enable, you can specify your own certificate. For further authentication solutions, you will need to create your own certificates using OpenSSL Tools for example.

 

Select common CA PEM

Select the certificate from the common Certificate Authority (CA). The syslog receiver should use the same CA.

 

Select Certificate PEM

Select the client certificate (PEM Format).

 

Select Key PEM

Select the keyfile for the client certificate (PEM Format).

 

 

 

TCP related Options

 

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TCP related Options

 

When using TCP-based syslog forwarding, you have the additional option to use the diskqueue. Whenever a connection to a remote syslog server fails, the action starts caching the syslog messages into temporary files. The folder for these files can be configured. The filenames are generated using a unique GUID which is automatically generated for each Action, thus enabling you to use this feature in multiple Actions. Once the syslog server becomes available again, the cached messages are being sent automatically. If you restart the Service while the Syslog Cache was active, it cannot be checked during service startup if the syslog server is available now. Once the action is called again, the check is done and if the syslog server is available, the messages are being sent. The size of this cache is only limited by the disk size. Files are splitted by 10MB by default, but this can also be configured. The maximum supported file size is 2GB.

 

Please Note: This option is not available for UDP or RFC3195.

 

 

 

UDP related Options

 

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UDP related Options

 

Enable IP Spoofing for the UDP Protocol

 

This option enables you to spoof the IP Address when sending Syslog messages over UDP. Some notes regarding the support of IP Spoofing. It is only supported the UDP Protocol and IPv4. IPv6 is not possible yet. Due system limitations introduced by Microsoft, IP Spoofing is only possible on Windows Server 2003, 2008 or higher. It is NOT possible in Windows XP, VISTA, 7 or higher. For more information see the Microsoft explanation. Also please note that most routers and gateways may drop network packages with spoofed IP Addresses, so it may only work in local networks.

 

Fixed IP or single property

 

You can either use a static IP Address or a property. When using a property, the IP Address is tried to be resolved from the content of the property. For example by default the %source% property is used. If the name in this property cannot be resolved to an IP Address, the default local IP Address will be used.

 

Note on Using Syslog Compression

 

Compressing syslog messages is an experimental feature. There is only a very limited set of receivers who is able to understand that format. Turning on compression can save valuable bandwidth in low-bandwidth environments. Depending on the message, the saving can be anything from no saving at all to about a reduction in half. The best savings ratios have been seen with Windows event log records in XML format. In this case, 50% or even a bit more can be saved. Very small messages do not compress at all. Typical syslog traffic in non-xml format is expected to compress around 10 to 25%.

 

Please note that compressesion over TCP connections requires a special transfer mode. This mode bases on an upcoming IETF standard (syslog-transport-tls) that is not yet finalized. That transfer mode is highly experimental in itself. As a result, future releases of our product might not be able to work with the current implementation. So there is a chance that you need to exchange all parts of the syslog/TCP system in future releases. Backwards compatibility can not be guaranteed.

 

Besides the fact that the mechanisms behind compression are experimental, the feature itself is solid.