ICAgent

This section describes the restrictions on the log collector ICAgent.

**Table 1** ICAgent file collection restrictions
Item	Description	Remarks
File encoding	UTF 8 is supported. Other encoding formats may cause garbled characters. You can configure whether to collect log files containing binary content. Binary characters may be displayed as garbled characters.	N/A
Host type	Only logs of Linux hosts can be collected.	N/A
Log file size	Unlimited	N/A
Log file rotation	ICAgent supports configuration of fixed log file names or fuzzy match of log file names. You need to rotate log files manually.	N/A
Log collection path	Linux Collection paths support recursion. You can use double asterisks () to collect logs from up to five directory levels. Example: /var/logs//a.log Collection paths support fuzzy match. You can use an asterisk () to represent one or more characters of a directory or file name. Example: /var/logs//a.log or /var/logs/service/a.log* If the collection path is set to a directory, for example, /var/logs/, only .log, .trace, and .out files in the directory are collected. If the collection path is set to name of a text file, that file is directly collected. Each collection path must be unique. That is, the same path of the same host cannot be configured for different log groups and log streams.	N/A
Symbolic link	Symbolic links are not supported.	N/A
Single log size	Configure whether log splitting is supported. A log cannot exceed 500 KB. If a log exceeds 500 KB, the extra part will be truncated and discarded. If log splitting is enabled, a log exceeding 500 KB will be split into multiple logs for collection. For example, a 600 KB log will be split into a 500 KB log and a 100 KB log. Only Linux hosts and single-line logs are supported.	N/A
Regular expression	Perl regular expressions are supported.	N/A
File collection configuration	A file can be reported to only one log group and stream. If a file is configured for multiple log streams, only one configuration takes effect.	N/A
File opening	Files are opened when being read, and closed after being read.	N/A
First log collection	All logs are collected.	N/A

**Table 2** ICAgent performance specifications
Item	Description	Remarks
Log collection rate	Raw logs of a single node are collected at a rate up to 50 MB/s.	Service quality cannot be ensured if this limit is exceeded.
Monitored directories	Up to five levels of directories are supported, with up to 1000 files.	N/A
Monitored files	Container scenarios The ICAgent can collect a maximum of 20 log files from a volume mounting directory. The ICAgent can collect a maximum of 1000 standard container output log files. These files must be in JSON format. VM scenarios A maximum of 1000 files are supported.	N/A
Default resource restrictions	CPU: Max. two CPU cores Memory: Max. min{4 GB, Physical memory/2}. A restart is triggered if this memory limit is exceeded. "min{4 GB, Physical memory/2}" means that the smaller value between half of the physical memory and 4 GB is used.	N/A
Resource limit reached	A forcible restart is triggered. Logs may be lost or duplicate if rotated during the restart.	N/A
Agent installation, upgrade, or uninstallation	Unlimited	N/A

**Table 3** Other restrictions on ICAgent
Item	Description	Remarks
Configuration update	Configuration updates take effect in 1 to 3 minutes.	N/A
Dynamic configuration loading	Console configurations can be dynamically delivered. The update of one configuration does not affect other configurations.	N/A
Configurations	Unlimited	N/A
Tenant isolation	Tenants are isolated from each other by default.	N/A
Log collection delay	Normally, the delay from writing logs to the disk to collecting the logs is less than 2s (congestion not considered).	N/A
Log upload	File changes are read and uploaded immediately once detected. One or more logs can be uploaded a time.	N/A
Network error handling	Network exceptions trigger retries at an interval of 5s.	N/A
Resource quota used up	If the resources allocated to the ICAgent are insufficient due to massive amounts of logs, the ICAgent continues and retries upon a failure. Logs will be stacked if resources are still insufficient.	N/A
Max. retry timeout	Retry attempts are periodically made.	N/A
Status check	The collector status is monitored through heartbeat detection.	N/A
Checkpoint timeout	Checkpoints are automatically deleted if no updates are made within 12 hours.	N/A
Checkpoint saving	Checkpoints are updated if logs are reported successfully.	N/A
Checkpoint saving path	The default save path: /var/share/oss/manager/ICProbeAgent/internal/TRACE	N/A
Log loss Duplicate logs	ICAgent uses multiple mechanisms to ensure log collection reliability and prevent data loss. However, logs may be lost in the following scenarios: Log files are rotated at a high speed, for example, once per second. Logs cannot be forwarded due to improper system security settings or syslog itself. The container running time, for example, shorter than 30s, is extremely short. A single node generates logs at a high speed, exceeding the allowed transmit bandwidth or log collection speed. It is recommended that the log generation speed of a single node is lower than 50 MB/s. When the ICAgent is restarted, identical data may be collected around the restart time.	N/A