ALB Queries, Route53

• How can we see Traffic distribution across ALB IPs?

If enabled, the ALB access log file will take on the following syntax and the ip-address string will be the address of the ALB which handled the request:

bucket[/prefix]/AWSLogs/aws-account-id/elasticloadbalancing/region/yyyy/mm/dd/aws-account-id_elasticloadbalancing_region_load-balancer-id_end-time_ip-address_random-string.log.gz

• Does DNS lookup on Route53 level takes care of randomization/order change of IPs of ALB returned by Route53? If yes then can you shed some light on details like which algo it uses etc? To make it more clear, basic intent is to know that on every DNS lookup , IP addresses being used by ALB are being returned in same order, randomized order and if randomized order then by what means?

I assume you mean directing traffic via Route53 to the ALBs - you would typically choose a routing policy and route the traffic via alias to the ALB. The response of the DNS queries should then depend on the routing policy chosen.