diff --git a/convex/machines.ts b/convex/machines.ts
index 3ceed28..7b6a342 100644
--- a/convex/machines.ts
+++ b/convex/machines.ts
@@ -521,11 +521,13 @@ export const register = mutation({
     const now = Date.now()
     const metadataPatch = args.metadata && typeof args.metadata === "object" ? (args.metadata as Record<string, unknown>) : undefined
 
+    // Busca 1: fingerprint exato (tenant + slug + hostname + MACs hash)
     let existing = await ctx.db
       .query("machines")
       .withIndex("by_tenant_fingerprint", (q) => q.eq("tenantId", tenantId).eq("fingerprint", fingerprint))
       .first()
 
+    // Busca 2: por email + validacao de hardware (fallback se fingerprint mudou mas email igual)
     if (!existing) {
       const collaboratorEmail = extractCollaboratorEmail(metadataPatch ?? args.metadata)
       if (collaboratorEmail) {
@@ -539,6 +541,40 @@ export const register = mutation({
       }
     }
 
+    // Busca 3: por hostname + validacao de hardware (fallback se o usuario mudou mas e a mesma maquina fisica)
+    // Isso garante que o historico de tickets da maquina seja preservado independente do usuario
+    if (!existing) {
+      const hostnameLower = args.hostname.trim().toLowerCase()
+      const candidates = await ctx.db
+        .query("machines")
+        .withIndex("by_tenant_hostname", (q) => q.eq("tenantId", tenantId).eq("hostname", args.hostname))
+        .collect()
+      // Procura uma maquina com hostname igual E hardware compativel (MAC ou serial)
+      for (const candidate of candidates) {
+        if (matchesExistingHardware(candidate, identifiers, args.hostname)) {
+          existing = candidate
+          break
+        }
+      }
+      // Se nao encontrou por hostname exato, tenta busca mais ampla por hardware
+      if (!existing) {
+        // Busca maquinas do mesmo tenant e verifica se alguma tem MAC/serial compativel
+        const allMachines = await ctx.db
+          .query("machines")
+          .withIndex("by_tenant", (q) => q.eq("tenantId", tenantId))
+          .collect()
+        for (const candidate of allMachines) {
+          // Verifica se compartilha MAC ou serial (hardware fisico)
+          const sharedMac = candidate.macAddresses.some((mac) => identifiers.macs.includes(mac))
+          const sharedSerial = candidate.serialNumbers.some((serial) => identifiers.serials.includes(serial))
+          if (sharedMac || sharedSerial) {
+            existing = candidate
+            break
+          }
+        }
+      }
+    }
+
     let machineId: Id<"machines">
 
     if (existing) {
diff --git a/convex/schema.ts b/convex/schema.ts
index e119888..7589ba0 100644
--- a/convex/schema.ts
+++ b/convex/schema.ts
@@ -647,6 +647,7 @@ export default defineSchema({
     .index("by_tenant_company", ["tenantId", "companyId"])
     .index("by_tenant_fingerprint", ["tenantId", "fingerprint"])
     .index("by_tenant_assigned_email", ["tenantId", "assignedUserEmail"])
+    .index("by_tenant_hostname", ["tenantId", "hostname"])
     .index("by_auth_email", ["authEmail"]),
 
   usbPolicyEvents: defineTable({