Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for dynamically activating and deactivating random-access channel (RACH) occasions (ROs). A base station may configure one or more ROs on which a user equipment (UE) can transmit RACH messages. If higher priority signaling (e.g., downlink signaling or uplink signaling) overlaps in time with the ROs, the base station may deactivate one or more ROs to decrease the likelihood of self-interference or cross-link interference (e.g., if the UE or the base station are operating in full duplex mode). The base station may deactivate or activate ROs by indicating indices for one or more ROs, indices for one or more synchronization signal blocks (SSBs), a pattern of ROs, some or all ROs within a time period, some or all ROs until a next downlink signal updates the RO configuration or activates ROs, or any combination thereof.