SONIC VLAN配置流程
sonic vlan配置通过订阅config_db的键空间事件完成vlan配置信息从config_db到内核和硬件。config_db.json格式如下：
"VLAN": { "Vlan1000": { "vlanid": "1000" } }, "VLAN_MEMBER": { "Vlan1000|Ethernet16": { "tagging_mode": "untagged" } }, "VLAN_INTERFACE": { "Vlan1000|192.168.0.1/27": {} }, 在swss容器中存在一个vlanmgrd进行用于订阅config_db的vlan键空间，响应vlan配置，解析后将其同步到内核和app_db。由portsorch订阅app_db vlan事件，将其同步到asic-db，最终将其同步到硬件。VLAN_INTERFACE接口信息由intfmgr和intforch进行处理。
vlanmgr
该进程运行在swss容器中，用于订阅config_db的vlan键空间，响应vlan配置，解析后将其同步到内核和app_db。
该部分涉及文件：
vlanmgrd.cpp
vlanmgr.cpp
vlanmgr.h
class VlanMgr : public Orch{public: VlanMgr(DBConnector *cfgDb, DBConnector *appDb, DBConnector *stateDb, const vector<string> &tableNames); using Orch::doTask;private: ProducerStateTable m_appVlanTableProducer, m_appVlanMemberTableProducer; Table m_cfgVlanTable, m_cfgVlanMemberTable; Table m_statePortTable, m_stateLagTable; Table m_stateVlanTable; std::set<std::string> m_vlans; void doTask(Consumer &consumer);//主任务 void doVlanTask(Consumer &consumer);//处理vlan事件 void doVlanMemberTask(Consumer &consumer);//处理vlan成员事件 void processUntaggedVlanMembers(string vlan, const string &members);//处理vlan内untag成员，暂时没用 bool addHostVlan(int vlan_id);//将vlan同步到host，即创建vlan bool removeHostVlan(int vlan_id);//删除host中的vlan bool setHostVlanAdminState(int vlan_id, const string &admin_status);//设置hostvlan状态 bool setHostVlanMtu(int vlan_id, uint32_t mtu);//设置host vlan接口的mtu //添加成员 bool addHostVlanMember(int vlan_id, const string &port_alias, const string& tagging_mode); bool removeHostVlanMember(int vlan_id, const string &port_alias);//删除host vlan成员 bool isMemberStateOk(const string &alias);//从state db中获取成员端口是否ok bool isVlanStateOk(const string &alias);//从state db中获取vlan是否ok bool isVlanMacOk();//判断该vlan的mac地址是否ok};实现
int main(int argc, char **argv){ Logger::linkToDbNative("vlanmgrd"); SWSS_LOG_ENTER(); SWSS_LOG_NOTICE("--- Starting vlanmgrd ---"); try { vector<string> cfg_vlan_tables = {//订阅了两个config db table CFG_VLAN_TABLE_NAME, CFG_VLAN_MEMBER_TABLE_NAME, }; //连接了三个数据库 DBConnector cfgDb(CONFIG_DB, DBConnector::DEFAULT_UNIXSOCKET, 0);//读和订阅config-db数据 DBConnector appDb(APPL_DB, DBConnector::DEFAULT_UNIXSOCKET, 0);//将配置希尔app-db DBConnector stateDb(STATE_DB, DBConnector::DEFAULT_UNIXSOCKET, 0);//获取vlan端口是否准备好 /* * swss service starts after interfaces-config.service which will have * switch_mac set. * Dynamic switch_mac update is not supported for now. * 获取全局的mac地址作为vlan-if的mac地址 */ Table table(&cfgDb, "DEVICE_METADATA"); std::vector<FieldValueTuple> ovalues; table.get("localhost", ovalues); auto it = std::find_if( ovalues.begin(), ovalues.end(), [](const FieldValueTuple& t){ return t.first == "mac";} ); if ( it == ovalues.end() ) { throw runtime_error("couldn't find MAC address of the device from config DB"); } gMacAddress = MacAddress(it->second); //构造vlanmgr VlanMgr vlanmgr(&cfgDb, &appDb, &stateDb, cfg_vlan_tables); std::vector<Orch *> cfgOrchList = {&vlanmgr}; swss::Select s; for (Orch *o : cfgOrchList) { s.addSelectables(o->getSelectables()); } SWSS_LOG_NOTICE("starting main loop"); while (true) { Selectable *sel; int ret; ret = s.select(&sel, SELECT_TIMEOUT); if (ret == Select::ERROR) { SWSS_LOG_NOTICE("Error: %s!", strerror(errno)); continue; } if (ret == Select::TIMEOUT) { vlanmgr.doTask(); continue; } auto *c = (Executor *)sel; c->execute(); } } catch(const std::exception &e) { SWSS_LOG_ERROR("Runtime error: %s", e.what()); } return -1;}VlanMgr::doTask(Consumer &consumer)
//vlanmgr主任务，vlan没有sync进程监听内核的netlink事件，内核与硬件的vlan事件都//由vlanmgr负责，vlanmgr负责在linux内核创建vlan和vlan-member，同时往app-db中写入//vlan事件。同时vlanif的IP地址在intfmgr中进行添加，并同步到内核void VlanMgr::doTask(Consumer &consumer){ SWSS_LOG_ENTER(); //获取事件表格名 string table_name = consumer.getTableName(); if (table_name == CFG_VLAN_TABLE_NAME) { doVlanTask(consumer);//vlan添加创建 } else if (table_name == CFG_VLAN_MEMBER_TABLE_NAME) { doVlanMemberTask(consumer);//vlan成员添加创建 } else { SWSS_LOG_ERROR("Unknown config table %s ", table_name.c_str()); throw runtime_error("VlanMgr doTask failure."); }}VlanMgr::doVlanTask(Consumer &consumer)
//执行vlan事件void VlanMgr::doVlanTask(Consumer &consumer){ if (!isVlanMacOk())//vlanmac是否准备好了，没有的话等待，这里就是个判断，vlanmac在vlanmgr起来时已经获取了 { SWSS_LOG_DEBUG("VLAN mac not ready, delaying VLAN task"); return; } auto it = consumer.m_toSync.begin(); while (it != consumer.m_toSync.end()) { auto &t = it->second; string key = kfvKey(t); /* Ensure the key starts with "Vlan" otherwise ignore */ if (strncmp(key.c_str(), VLAN_PREFIX, 4)) { SWSS_LOG_ERROR("Invalid key format. No 'Vlan' prefix: %s", key.c_str()); it = consumer.m_toSync.erase(it); continue; } int vlan_id; vlan_id = stoi(key.substr(4)); string vlan_alias, port_alias; string op = kfvOp(t); if (op == SET_COMMAND) { string admin_status; uint32_t mtu = 0; vector<FieldValueTuple> fvVector; string members; /* Add host VLAN when it has not been created. */ //添加vlan if (m_vlans.find(key) == m_vlans.end()) { addHostVlan(vlan_id); } /* set up host env .... */ //设置host vlan相关信息 for (auto i : kfvFieldsValues(t)) { /* Set vlan admin status 设置管理状态*/ if (fvField(i) == "admin_status") { admin_status = fvValue(i); setHostVlanAdminState(vlan_id, admin_status); fvVector.push_back(i); } /* Set vlan mtu 设置mtu */ else if (fvField(i) == "mtu") { mtu = (uint32_t)stoul(fvValue(i)); /* * TODO: support host VLAN mtu setting. * Host VLAN mtu should be set only after member configured * and VLAN state is not UNKNOWN. */ SWSS_LOG_DEBUG("%s mtu %u: Host VLAN mtu setting to be supported.", key.c_str(), mtu); fvVector.push_back(i); } else if (fvField(i) == "members@") { members = fvValue(i); } } /* fvVector should not be empty */ if (fvVector.empty()) { FieldValueTuple a("admin_status", "up"); fvVector.push_back(a); } //写入app-db m_appVlanTableProducer.set(key, fvVector); m_vlans.insert(key); //写入state-db(6) fvVector.clear(); FieldValueTuple s("state", "ok"); fvVector.push_back(s); m_stateVlanTable.set(key, fvVector); it = consumer.m_toSync.erase(it); /* * Members configured together with VLAN in untagged mode. * This is to be compatible with access VLAN configuration from minigraph. * untag模式配置vlan时，会跟随着vlan一起下发，所以在这里解决vlan成员添加问题。 * tag vlan则在单独的mem表中添加。 */ if (!members.empty()) { processUntaggedVlanMembers(key, members); } } else if (op == DEL_COMMAND)//删除 { if (m_vlans.find(key) != m_vlans.end()) { removeHostVlan(vlan_id);//找到删除 m_vlans.erase(key); m_appVlanTableProducer.del(key);//通知app-db m_stateVlanTable.del(key);//删除状态 } else { SWSS_LOG_ERROR("%s doesn't exist", key.c_str()); } SWSS_LOG_DEBUG("%s", (dumpTuple(consumer, t)).c_str()); it = consumer.m_toSync.erase(it); } else { SWSS_LOG_ERROR("Unknown operation type %s", op.c_str()); SWSS_LOG_DEBUG("%s", (dumpTuple(consumer, t)).c_str()); it = consumer.m_toSync.erase(it); } }}void VlanMgr::doVlanMemberTask(Consumer &consumer)
//处理vlan-member事件void VlanMgr::doVlanMemberTask(Consumer &consumer){ auto it = consumer.m_toSync.begin(); while (it != consumer.m_toSync.end()) { auto &t = it->second; string key = kfvKey(t); /* Ensure the key starts with "Vlan" otherwise ignore */ if (strncmp(key.c_str(), VLAN_PREFIX, 4)) { SWSS_LOG_ERROR("Invalid key format. No 'Vlan' prefix: %s", key.c_str()); it = consumer.m_toSync.erase(it); continue; } key = key.substr(4); size_t found = key.find(CONFIGDB_KEY_SEPARATOR); int vlan_id; string vlan_alias, port_alias; if (found != string::npos) { vlan_id = stoi(key.substr(0, found)); port_alias = key.substr(found+1); } else { SWSS_LOG_ERROR("Invalid key format. No member port is presented: %s", kfvKey(t).c_str()); it = consumer.m_toSync.erase(it); continue; } //获取vlan名字 vlan_alias = VLAN_PREFIX + to_string(vlan_id); string op = kfvOp(t); // TODO: store port/lag/VLAN data in local data structure and perform more validations. if (op == SET_COMMAND) { /* Don't proceed if member port/lag is not ready yet */ if (!isMemberStateOk(port_alias) || !isVlanStateOk(vlan_alias)) { SWSS_LOG_DEBUG("%s not ready, delaying", kfvKey(t).c_str()); it++; continue; } string tagging_mode = "untagged"; for (auto i : kfvFieldsValues(t)) { if (fvField(i) == "tagging_mode") { tagging_mode = fvValue(i); } } if (tagging_mode != "untagged" && tagging_mode != "tagged" && tagging_mode != "priority_tagged") { SWSS_LOG_ERROR("Wrong tagging_mode '%s' for key: %s", tagging_mode.c_str(), kfvKey(t).c_str()); it = consumer.m_toSync.erase(it); continue; } //添加vlan成员 if (addHostVlanMember(vlan_id, port_alias, tagging_mode)) { key = VLAN_PREFIX + to_string(vlan_id); key += DEFAULT_KEY_SEPARATOR; key += port_alias;//写入app-db数据库 m_appVlanMemberTableProducer.set(key, kfvFieldsValues(t)); } it = consumer.m_toSync.erase(it); } else if (op == DEL_COMMAND) { removeHostVlanMember(vlan_id, port_alias); key = VLAN_PREFIX + to_string(vlan_id); key += DEFAULT_KEY_SEPARATOR; key += port_alias; m_appVlanMemberTableProducer.del(key); SWSS_LOG_DEBUG("%s", (dumpTuple(consumer, t)).c_str()); it = consumer.m_toSync.erase(it); } else { SWSS_LOG_ERROR("Unknown operation type %s", op.c_str()); it = consumer.m_toSync.erase(it); } }}同步app_db数据到asic_db
app_db的vlan事件由portsorch进行同步，该部分涉及文件：
portsorch.cpp
portsorch.h
app_db中数据样例：
127.0.0.1:6379> KEYS *VLAN*1) "VLAN_TABLE:Vlan1000"2) "VLAN_MEMBER_TABLE:Vlan1000:Ethernet16"127.0.0.1:6379> HGETALL "VLAN_MEMBER_TABLE:Vlan1000:Ethernet16"1) "tagging_mode"2) "untagged"127.0.0.1:6379> HGETALL "VLAN_TABLE:Vlan1000"1) "admin_status"2) "up"127.0.0.1:6379> void PortsOrch::doTask(Consumer &consumer)
void PortsOrch::doTask(Consumer &consumer){ SWSS_LOG_ENTER(); string table_name = consumer.getTableName(); if (table_name == APP_PORT_TABLE_NAME) { doPortTask(consumer); } else { /* Wait for all ports to be initialized */ if (!isInitDone()) { return; } if (table_name == APP_VLAN_TABLE_NAME)//处理vlan { doVlanTask(consumer); } else if (table_name == APP_VLAN_MEMBER_TABLE_NAME)//处理vlan成员 { doVlanMemberTask(consumer); } else if (table_name == APP_LAG_TABLE_NAME) { doLagTask(consumer); } else if (table_name == APP_LAG_MEMBER_TABLE_NAME) { doLagMemberTask(consumer); } }}void PortsOrch::doVlanTask(Consumer &consumer)
void PortsOrch::doVlanTask(Consumer &consumer){ SWSS_LOG_ENTER(); auto it = consumer.m_toSync.begin(); while (it != consumer.m_toSync.end()) { auto &t = it->second; string key = kfvKey(t); /* Ensure the key starts with "Vlan" otherwise ignore */ if (strncmp(key.c_str(), VLAN_PREFIX, 4)) { SWSS_LOG_ERROR("Invalid key format. No 'Vlan' prefix: %s", key.c_str()); it = consumer.m_toSync.erase(it); continue; } int vlan_id; vlan_id = stoi(key.substr(4)); // FIXME: might raise exception string vlan_alias, port_alias; vlan_alias = VLAN_PREFIX + to_string(vlan_id); string op = kfvOp(t); if (op == SET_COMMAND) { /* * Only creation is supported for now. * We may add support for VLAN mac learning enable/disable, * VLAN flooding control setting and etc. in the future. * 创建一个vlan */ if (m_portList.find(vlan_alias) == m_portList.end()) { if (!addVlan(vlan_alias)) { it++; continue; } } it = consumer.m_toSync.erase(it); } else if (op == DEL_COMMAND) { Port vlan; getPort(vlan_alias, vlan); if (removeVlan(vlan)) it = consumer.m_toSync.erase(it); else it++; } else { SWSS_LOG_ERROR("Unknown operation type %s", op.c_str()); it = consumer.m_toSync.erase(it); } }}void PortsOrch::doVlanMemberTask(Consumer &consumer)
void PortsOrch::doVlanMemberTask(Consumer &consumer){ SWSS_LOG_ENTER(); auto it = consumer.m_toSync.begin(); while (it != consumer.m_toSync.end()) { auto &t = it->second; string key = kfvKey(t); /* Ensure the key starts with "Vlan" otherwise ignore */ if (strncmp(key.c_str(), VLAN_PREFIX, 4)) { SWSS_LOG_ERROR("Invalid key format. No 'Vlan' prefix: %s", key.c_str()); it = consumer.m_toSync.erase(it); continue; } key = key.substr(4); size_t found = key.find(':'); int vlan_id; string vlan_alias, port_alias; if (found != string::npos) { vlan_id = stoi(key.substr(0, found)); // FIXME: might raise exception port_alias = key.substr(found+1); } else { SWSS_LOG_ERROR("Invalid key format. No member port is presented: %s", kfvKey(t).c_str()); it = consumer.m_toSync.erase(it); continue; } //vlan名字 vlan_alias = VLAN_PREFIX + to_string(vlan_id); string op = kfvOp(t); assert(m_portList.find(vlan_alias) != m_portList.end()); Port vlan, port; /* When VLAN member is to be created before VLAN is created */ if (!getPort(vlan_alias, vlan)) { SWSS_LOG_INFO("Failed to locate VLAN %s", vlan_alias.c_str()); it++; continue; } if (!getPort(port_alias, port)) { SWSS_LOG_DEBUG("%s is not not yet created, delaying", port_alias.c_str()); it++; continue; } if (op == SET_COMMAND) { string tagging_mode = "untagged"; for (auto i : kfvFieldsValues(t)) { if (fvField(i) == "tagging_mode") tagging_mode = fvValue(i); } if (tagging_mode != "untagged" && tagging_mode != "tagged" && tagging_mode != "priority_tagged") { SWSS_LOG_ERROR("Wrong tagging_mode '%s' for key: %s", tagging_mode.c_str(), kfvKey(t).c_str()); it = consumer.m_toSync.erase(it); continue; } /* Duplicate entry */ if (vlan.m_members.find(port_alias) != vlan.m_members.end()) { it = consumer.m_toSync.erase(it); continue; } //加入vlan的端口将会创建一个桥接口，桥接口是一个二层口的抽象，屏蔽lag，phy等接口的差异 if (addBridgePort(port) && addVlanMember(vlan, port, tagging_mode)) it = consumer.m_toSync.erase(it); else it++; } else if (op == DEL_COMMAND) { if (vlan.m_members.find(port_alias) != vlan.m_members.end()) { if (removeVlanMember(vlan, port)) { if (port.m_vlan_members.empty()) { removeBridgePort(port); } it = consumer.m_toSync.erase(it); } else { it++; } } else /* Cannot locate the VLAN */ it = consumer.m_toSync.erase(it); } else { SWSS_LOG_ERROR("Unknown operation type %s", op.c_str()); it = consumer.m_toSync.erase(it); } }}配置host vlan步骤
sudo ip link add Bridge type bridge up #创建一个网桥，等价于sudo brctl addbr Bridgesudo bridge vlan add vid 6 dev Bridge self #给网桥创建一个vlan表项，vid为6 #创建一个vlan虚接口，其附着在Bridge接口上，设置其mac为00:00:00:00:00:01，这是一个vlan-if接口sudo ip link add link Bridge up name Vlan6 address 00:00:00:00:00:01 type vlan id 6 #将网卡添加到Bridge中，等价于命令sudo brctl addif Bridge Ethernet32sudo ip link set Ethernet32 master Bridge#配置网卡Ethernet32以tagged模式加入vlan6sudo bridge vlan add vid 6 dev Ethernet32 tagged查看vlan配置
admin@switch:~$ sudo bridge vlanport vlan idsdocker0 NoneBridge 6Ethernet32 6admin@switch:~$ 从上面可以看出，有两个设备加入了vlan6：Bridge和Ethernet32
VLAN基本知识补充
TAG 字段由4个字节组成，前两个字节为TPID（TAG Protocol Identifier），其值固定为0x8100，表示是dot1q标准的TAG。后两个字节为TCI（TAG Control Information），它又分为三个部分，图示如下：
1）user_priority：用户优先级，占3个比特，可以表示8种不同的优先级，不同优先级的报文可以得到不同级别的服务；
2）CFI：规范格式指示符（Canonical Format Indicator），占一个比特，它通常设置为0，表示报文中的MAC地址格式为规范格式（遵循IEEE 802标准，即字节中的比特位顺序与标准一致），如果该位设置为1，则根据网络类型的不同具有不同的意义，具体可以参考dot1q标准文档。
3）VID：即VLAN的标志符，占12个比特，表示一个无符号整数，范围从0～4095，其中0表示报文没有指定的VID（priority tagged），4095按规定是保留的，不能使用，交换机收到这样的报文不会进行转发，因此可用的VID范围为1～4094，这其中VID 1又规定为默认VLAN，在用户没有配置的情况下，设备的出厂配置是所有端口属于VLAN 1，端口的默认VID也是VLAN 1。vid为0的帧(即priority tagged帧)用于指定优先级，但不指定vid，当接口收到这种报文后，会将vid设置为pvid
4）pvid 不是加在帧头的标记，而是端口的属性。
5）pvid 是 用来标识端口接收到的未标记的帧。
也就是说，当端口收到一个未标记的帧时，就把该帧打上vlan id，这个id值等于pvid的值，然后转发到VID和PVID相等的VLAN 中。
6）帧从端口出去时，如果帧头中的VID和端口的PVID值相同，就把这个标识去掉，再送出去。
7）如果端口为access类型，并加入了一个vlan ，那么这端口的PVID属性值变成和VID值一样,如果不一样就会把帧送到错误的vlan中，导致通行中断。但在trunk型的端口里，pvid的值是默认的1，注意交换机默认的vid也是1，所以交换机vlan id 为1的端口向trunk端口转发数据包时，trunk端口的把帧头的标识去掉再发出去，到了对方交换机trunk口时，由于帧没有带标识，所以会加上个vid,其值为1（因为trunk端口默认的pvid为1），这样数据包就 会被正确的送到vlan id为1的端口中。
所以没有划分vlan的端口发出的数据包也能通过trunk端口发出去，可以正常通行。而不是不能通过trunk口。
8 )Hybrid的输入输出端口对数据包的处理：
接收端口：同时都能够接收VID=PVID和VID=PVID的taggedframe，不改变TAG；对于untagedframe则加上端口的PVID和 defaultpriority再进行交换转发，对于priority only taggedframe则添加PVID再进行转发。接收方向与trunk口行为一致。
发送端口： 1、判断该VLAN在本端口的属性
2、如果是untag则剥离VLAN信息，再发送，如果是tag则比较端口的PVID和将要发送报文的VLAN信息，如果两 者相等则剥离VLAN信息，再发送，否则报文将携带原有的VLAN标记进行转发。
Hybrid接口可以配置多个untagged vlan，这是与trunk端口最大的不同。