# Istio Agent

This document describes the internal architecture of Istio agent.

## High Level overview

![High Level overview](docs/overview.svg)

At a high level, the Istio agent acts as an intermediate proxy between Istiod and Envoy. This is done
at two levels. For distributing workload certificates, Envoy will send [SDS](https://www.envoyproxy.io/docs/envoy/latest/configuration/security/secret)

  -d | -debug        Set sbt log level to debug
  -mem <integer>     Set memory options (default: $sbt_mem, which is $(get_mem_opts $sbt_mem))
  -jvm-debug <port>  Turn on JVM debugging, open at the given port.

  # java version (default: java from PATH, currently $(java -version 2>&1 | grep version))
  -java-home <path>  Alternate JAVA_HOME

  # jvm options and output control

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 * you may not use this file except in compliance with the License.
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 * Copyright 2012-2024 CodeLibs Project and the Others.
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 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
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 *
 * Unless required by applicable law or agreed to in writing, software
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 * Copyright 2012-2024 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
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 *
 * Unless required by applicable law or agreed to in writing, software
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 * Copyright 2012-2024 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

 * Copyright 2012-2024 CodeLibs Project and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
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