LXC Logging

1. Guest OS enables /dev/ttyS2 on Guest application.

2. Guest application writes data to /dev/ttyS2.

3. Libvert emulates /dev/ttyS2 to /dev/pts/x on the host.

4. IOXMAN gets the emulated serial device, /dev/pts/x from the XML file.

5. IOXMAN listens and reads available data from /dev/pts/x, sets the severity for the message, filters, parses and queues the message.

6. Start timer to send the message to /dev/log device on the host using errmsg.

7. Data is saved to IOS syslog.

KVM Logging

1. Guest OS enables /dev/ttyS2 on Guest application.

2. Guest application writes data to /dev/ttyS2.

3. Libvert emulates /dev/ttyS2 to /dev/pts/x on the host.

4. IOXMAN gets the emulated TCP path from the XML file.

5. IOXMAN opens an unix socket, and connects to the remote socket.

6. IOXMAN reads available data from the socket, sets the severity for the message, filters, parses, and queues the message.

7. Start timer to send the message to /dev/log device on the host using errmsg.

8. Data is saved to IOS syslog.

LXC Tracing

1. Guest OS enables /dev/ttyS3 on Guest application.

2. Configures syslogd to copy message to /dev/ttyS3.

3. Guest application writes data to /dev/ttyS3.

4. Libvert emulates /dev/ttyS3 to /dev/pts/y on the host.

5. IOXMAN gets the emulated serial device, /dev/pts/y from the XML file.

6. IOXMAN listens and reads available data from /dev/pts/y, filters, parses, and saves the message to IOx tracelog.

7. If IOx tracelog is full, IOXMAN rotates the tracelog file to /bootflash/tracelogs.

KVM Tracing

1. Guest OS enables /dev/ttyS3 on Guest application.

2. Configures syslogd to copy message to /dev/ttyS3.

3. Guest application writes data to /dev/ttyS3.

4. Libvert emulates /dev/ttyS3 to TCP path on the host.

5. IOXMAN gets the emulated TCP path from the XML file.

6. IOXMAN opens an unix socket, and connects to the remote socket.

7. IOXMAN reads available data from the scoket, sets the severity for the message, filters, parses, and saves the message to IOx tracelog.

8. If IOx tracelog is full, IOXMAN rotates the tracelog file to /bootflash/tracelogs.

Logging Messages in IOS Syslog

For any logging messages received from the Guest Application, IOXMAN sets the severity of the message to NOTICE by default, before sending it to IOS syslog. When a message is received by IOSd, it is displayed on the console and saved on the IOS syslog in the following message format.

In order to comply with IOS syslog, IOXMAN does support severity for logging message. To report logging message with severity, Guest Application needs to append the header to the front of the message.

[a123b234,version,severity]

a123b234 is magic number.
Version:        severity support version.  Current version is 1.
Severity:       CRIT is 2
                ERR is 3
                WARN is 4
                NOTICE is 5
                INFO is 6
                DEBUG is 7

Following is an example of a messge log:

echo “[a123b234,1,2]Guestshell failed” > /dev/ttyS2

Perform the following steps to report logging data from Guest Application to IOS syslog:

1. If you are using C programming, use write() to send logging data to host.

   #define SYSLOG_TEST       “syslog test”
        int fd;
        fd = open("/dev/ttyS2", O_WRONLY);
        write(fd, SYSLOG_TEST, strlen(SYSLOG_TEST));
        close(fd);
   
   

2. If you are using Shell console, use echo to send logging data to host.

   echo “syslog test” > /dev/ttyS2
   
   

Tracing Message to IOx Tracelog

Perform the following steps to report tracing messages from Guest Application to IOx tracelog:

1. If you are using C programming, use write() to send tracing message to host.

   #define SYSLOG_TEST       “tracelog test”
        int fd;
        fd = open("/dev/ttyS3", O_WRONLY);
        write(fd, SYSLOG_TEST, strlen(SYSLOG_TEST));
        close(fd);
   
   

2. If you are using C programming, use syslog() to send tracing message to host.

   #define SYSLOG_TEST       “tracelog test”
   
   syslog(LOG_INFO, “%s\n”, SYSLOG_TEST);
   
   

3. If you are using Shell console, use echo to send tracing data to host.

   echo “tracelog test” > /dev/ttyS3   
      or
   logger “tracelog test”