diff --git a/server/routers/gerbil/receiveBandwidth.ts b/server/routers/gerbil/receiveBandwidth.ts
index e06a6d5d0..b73ce986d 100644
--- a/server/routers/gerbil/receiveBandwidth.ts
+++ b/server/routers/gerbil/receiveBandwidth.ts
@@ -97,7 +97,6 @@ export async function flushSiteBandwidthToDb(): Promise<void> {
     accumulator = new Map<string, AccumulatorEntry>();
 
     const currentTime = new Date().toISOString();
-    const currentTimeEpochSeconds = Math.floor(new Date().getTime() / 1000);
 
     // Sort by publicKey for consistent lock ordering across concurrent
     // writers — deadlock-prevention strategy.
@@ -121,7 +120,6 @@ export async function flushSiteBandwidthToDb(): Promise<void> {
                         megabytesOut: sql`COALESCE(${sites.megabytesOut}, 0) + ${bytesIn}`,
                         megabytesIn: sql`COALESCE(${sites.megabytesIn}, 0) + ${bytesOut}`,
                         lastBandwidthUpdate: currentTime,
-                        lastPing: currentTimeEpochSeconds
                     })
                     .where(eq(sites.pubKey, publicKey))
                     .returning({
diff --git a/server/routers/integration.ts b/server/routers/integration.ts
index a36a61e84..e5c76aa4a 100644
--- a/server/routers/integration.ts
+++ b/server/routers/integration.ts
@@ -309,6 +309,14 @@ authenticated.post(
     siteResource.removeClientFromSiteResource
 );
 
+authenticated.post(
+    "/client/:clientId/resources",
+    verifyLimits,
+    verifyApiKeyHasAction(ActionsEnum.setResourceUsers),
+    logActionAudit(ActionsEnum.setResourceUsers),
+    siteResource.batchAddClientToSiteResources
+);
+
 authenticated.put(
     "/org/:orgId/resource",
     verifyApiKeyOrgAccess,
diff --git a/server/routers/siteResource/batchAddClientToSiteResources.ts b/server/routers/siteResource/batchAddClientToSiteResources.ts
new file mode 100644
index 000000000..d71ca204a
--- /dev/null
+++ b/server/routers/siteResource/batchAddClientToSiteResources.ts
@@ -0,0 +1,247 @@
+import { Request, Response, NextFunction } from "express";
+import { z } from "zod";
+import {
+    db,
+    clients,
+    clientSiteResources,
+    siteResources,
+    apiKeyOrg
+} from "@server/db";
+import response from "@server/lib/response";
+import HttpCode from "@server/types/HttpCode";
+import createHttpError from "http-errors";
+import logger from "@server/logger";
+import { fromError } from "zod-validation-error";
+import { eq, and, inArray } from "drizzle-orm";
+import { OpenAPITags, registry } from "@server/openApi";
+import {
+    rebuildClientAssociationsFromClient,
+    rebuildClientAssociationsFromSiteResource
+} from "@server/lib/rebuildClientAssociations";
+
+const batchAddClientToSiteResourcesParamsSchema = z
+    .object({
+        clientId: z.string().transform(Number).pipe(z.number().int().positive())
+    })
+    .strict();
+
+const batchAddClientToSiteResourcesBodySchema = z
+    .object({
+        siteResourceIds: z
+            .array(z.number().int().positive())
+            .min(1, "At least one siteResourceId is required")
+    })
+    .strict();
+
+registry.registerPath({
+    method: "post",
+    path: "/client/{clientId}/resources",
+    description: "Add a machine client to multiple site resources at once.",
+    tags: [OpenAPITags.PrivateResource, OpenAPITags.Client],
+    request: {
+        params: batchAddClientToSiteResourcesParamsSchema,
+        body: {
+            content: {
+                "application/json": {
+                    schema: batchAddClientToSiteResourcesBodySchema
+                }
+            }
+        }
+    },
+    responses: {}
+});
+
+export async function batchAddClientToSiteResources(
+    req: Request,
+    res: Response,
+    next: NextFunction
+): Promise<any> {
+    try {
+        const apiKey = req.apiKey;
+        if (!apiKey) {
+            return next(
+                createHttpError(HttpCode.UNAUTHORIZED, "Key not authenticated")
+            );
+        }
+
+        const parsedParams =
+            batchAddClientToSiteResourcesParamsSchema.safeParse(req.params);
+        if (!parsedParams.success) {
+            return next(
+                createHttpError(
+                    HttpCode.BAD_REQUEST,
+                    fromError(parsedParams.error).toString()
+                )
+            );
+        }
+
+        const parsedBody = batchAddClientToSiteResourcesBodySchema.safeParse(
+            req.body
+        );
+        if (!parsedBody.success) {
+            return next(
+                createHttpError(
+                    HttpCode.BAD_REQUEST,
+                    fromError(parsedBody.error).toString()
+                )
+            );
+        }
+
+        const { clientId } = parsedParams.data;
+        const { siteResourceIds } = parsedBody.data;
+        const uniqueSiteResourceIds = [...new Set(siteResourceIds)];
+
+        const batchSiteResources = await db
+            .select()
+            .from(siteResources)
+            .where(
+                inArray(siteResources.siteResourceId, uniqueSiteResourceIds)
+            );
+
+        if (batchSiteResources.length !== uniqueSiteResourceIds.length) {
+            return next(
+                createHttpError(
+                    HttpCode.NOT_FOUND,
+                    "One or more site resources not found"
+                )
+            );
+        }
+
+        if (!apiKey.isRoot) {
+            const orgIds = [
+                ...new Set(batchSiteResources.map((sr) => sr.orgId))
+            ];
+            if (orgIds.length > 1) {
+                return next(
+                    createHttpError(
+                        HttpCode.BAD_REQUEST,
+                        "All site resources must belong to the same organization"
+                    )
+                );
+            }
+            const orgId = orgIds[0];
+            const [apiKeyOrgRow] = await db
+                .select()
+                .from(apiKeyOrg)
+                .where(
+                    and(
+                        eq(apiKeyOrg.apiKeyId, apiKey.apiKeyId),
+                        eq(apiKeyOrg.orgId, orgId)
+                    )
+                )
+                .limit(1);
+
+            if (!apiKeyOrgRow) {
+                return next(
+                    createHttpError(
+                        HttpCode.FORBIDDEN,
+                        "Key does not have access to the organization of the specified site resources"
+                    )
+                );
+            }
+
+            const [clientInOrg] = await db
+                .select()
+                .from(clients)
+                .where(
+                    and(
+                        eq(clients.clientId, clientId),
+                        eq(clients.orgId, orgId)
+                    )
+                )
+                .limit(1);
+
+            if (!clientInOrg) {
+                return next(
+                    createHttpError(
+                        HttpCode.FORBIDDEN,
+                        "Key does not have access to the specified client"
+                    )
+                );
+            }
+        }
+
+        const [client] = await db
+            .select()
+            .from(clients)
+            .where(eq(clients.clientId, clientId))
+            .limit(1);
+
+        if (!client) {
+            return next(
+                createHttpError(HttpCode.NOT_FOUND, "Client not found")
+            );
+        }
+
+        if (client.userId !== null) {
+            return next(
+                createHttpError(
+                    HttpCode.BAD_REQUEST,
+                    "This endpoint only supports machine (non-user) clients; the specified client is associated with a user"
+                )
+            );
+        }
+
+        const existingEntries = await db
+            .select({
+                siteResourceId: clientSiteResources.siteResourceId
+            })
+            .from(clientSiteResources)
+            .where(
+                and(
+                    eq(clientSiteResources.clientId, clientId),
+                    inArray(
+                        clientSiteResources.siteResourceId,
+                        batchSiteResources.map((sr) => sr.siteResourceId)
+                    )
+                )
+            );
+
+        const existingSiteResourceIds = new Set(
+            existingEntries.map((e) => e.siteResourceId)
+        );
+        const siteResourcesToAdd = batchSiteResources.filter(
+            (sr) => !existingSiteResourceIds.has(sr.siteResourceId)
+        );
+
+        if (siteResourcesToAdd.length === 0) {
+            return next(
+                createHttpError(
+                    HttpCode.CONFLICT,
+                    "Client is already assigned to all specified site resources"
+                )
+            );
+        }
+
+        await db.transaction(async (trx) => {
+            for (const siteResource of siteResourcesToAdd) {
+                await trx.insert(clientSiteResources).values({
+                    clientId,
+                    siteResourceId: siteResource.siteResourceId
+                });
+            }
+
+            await rebuildClientAssociationsFromClient(client, trx);
+        });
+
+        return response(res, {
+            data: {
+                addedCount: siteResourcesToAdd.length,
+                skippedCount:
+                    batchSiteResources.length - siteResourcesToAdd.length,
+                siteResourceIds: siteResourcesToAdd.map(
+                    (sr) => sr.siteResourceId
+                )
+            },
+            success: true,
+            error: false,
+            message: `Client added to ${siteResourcesToAdd.length} site resource(s) successfully`,
+            status: HttpCode.CREATED
+        });
+    } catch (error) {
+        logger.error(error);
+        return next(
+            createHttpError(HttpCode.INTERNAL_SERVER_ERROR, "An error occurred")
+        );
+    }
+}
diff --git a/server/routers/siteResource/index.ts b/server/routers/siteResource/index.ts
index 9494843bf..5c09d3883 100644
--- a/server/routers/siteResource/index.ts
+++ b/server/routers/siteResource/index.ts
@@ -15,4 +15,5 @@ export * from "./addUserToSiteResource";
 export * from "./removeUserFromSiteResource";
 export * from "./setSiteResourceClients";
 export * from "./addClientToSiteResource";
+export * from "./batchAddClientToSiteResources";
 export * from "./removeClientFromSiteResource";